90% of brands leave incremental growth on the table: do you know the modern marketing budget optimization framework?

As of 2026, the global marketing landscape faces unprecedented pressure, with recent research showing that 42% of marketers expect their annual budgets to be lower than previous cycles. This widespread budget contraction has pushed the need to prove incremental marketing value to a tipping point, leaving many leaders scrambling to justify every dollar of investment while lacking the structured frameworks and tools to make confident, data-backed allocation decisions, especially for teams running SEM and search engine marketing campaigns. Despite 71% of marketers increasing their focus on effectiveness tracking over the past three years, a significant "clarity gap" persists: 44% of marketers do not agree that marketing effectiveness is a well-defined function within their organizations. This uncertainty has pushed many brands toward short-termism, prioritizing easily measured immediate metrics at the expense of long-term growth drivers. Against this backdrop, new research and practical frameworks from Google and leading industry partners offer a clear path for brands to optimize budgets, unlock untapped growth, and outperform competitors in a constrained climate, even for brands focused heavily on SEM google and Google advertising.

1. The Context: Pressing Challenges for Modern Marketing Budget Optimization

Today’s marketing leaders operate in a landscape defined by shrinking budgets, fragmented customer journeys, and persistent measurement gaps that make strategic budget optimization far more complex than traditional approaches can address, and SEM search advertising teams face this complexity more acutely than most. The most immediate challenge comes from widespread budget contraction, with nearly half of all marketers projecting reduced budgets for the current year. This pressure to deliver more with less has elevated the stakes of proving incremental value for every investment, but the organizational clarity and tools needed to do this remain out of reach for most teams running search engine marketing and SEM initiatives. While a majority of marketers have increased their focus on effectiveness tracking in recent years, the clarity gap leaves nearly half of all teams unable to confidently define or measure marketing effectiveness within their business structures, including teams managing Google ads and Google advertising campaigns. This uncertainty creates a strong bias toward short-term thinking, as brands retreat to the perceived safety of immediate, easily tracked metrics and neglect the long-term brand building activities that drive sustained, profitable growth. Compounding this challenge is the growing fragmentation of marketing channels, as customers move fluidly across search, social, streaming, and offline touchpoints, rendering traditional individual-level tracking less effective and less privacy-compliant than ever before, even for well-established SEM search advertising strategies. Even for organizations that have adopted marketing mix modeling (MMM), a long-standing tool for measuring overall marketing impact, an "actionability gap" persists: while 87% of organizations recognize MMM as an important tool for their business, only 28% report that they are very effective at converting MMM insights into timely, actionable strategic decisions for SEM google and other core marketing channels. For brands investing in brand marketing, an additional layer of challenge exists: demand-generating brand channels often lack direct attribution, making it difficult to quantify their impact on sales and secure additional budget from finance teams, leaving strong growth potential on the table, even for high-performing Google ads campaigns. All of these overlapping challenges create an urgent need for a new approach to budget optimization that addresses the clarity gap, solves measurement challenges, and aligns budget allocation with actual customer demand across all channels, including SEM and search engine marketing.

2. Core Concept: The Marketing Saturation Curve Framework Explained

To address the growing clarity gap in budget optimization, Google and leading analytics firm Ekimetrics have developed a structured growth blueprint built around the marketing saturation curve framework, which is rooted in the universal S-curve law of investment returns, and this framework works exceptionally well for planning SEM search advertising and Google advertising spend. This framework clarifies the non-linear relationship between marketing spend and business outcomes, replacing simplistic linear assumptions about spend and return with a nuanced model that reflects how marketing actually delivers growth in practice, including growth from SEM and search engine marketing. In this framework, the horizontal axis represents "effort", which in a marketing context refers to core inputs such as advertising spend, level of media activity, and other measures of overall media intensity, including total spend allocated to SEM google campaigns. The vertical axis represents "gain", which refers to desired marketing outcomes, most commonly incremental sales or revenue over both short and long time horizons, but can also include other key performance indicators such as brand awareness, website engagement, and lead generation for Google ads. Every marketing saturation curve is divided into five critical zones that each describe the impact of additional spend in a distinct part of the curve. The first is the wear-in zone, where revenue grows more slowly than spend due to initial friction, the process of building audience awareness, and the natural length of customer purchase cycles; in this zone, brands invest through temporary inefficiency to reach the scale needed for sustained profitable growth, a dynamic that plays out regularly for new SEM search advertising campaigns. The second zone is the acceleration zone, where brands have crossed the break-even threshold, and every additional dollar of spend generates profit, with efficiency improving with each additional investment, creating the steepest period of overall growth for search engine marketing and SEM campaigns alike. Third is the efficiency zone, where brands have passed the inflection point where marginal returns begin to diminish, but returns remain high enough to continue pulling the overall average return-on-ad-spend (ROAS) upward, a sweet spot many experienced Google advertising teams target. Fourth is the contribution zone, where total ROAS has peaked and begins to decline, but every additional dollar of spend still increases total revenue and profit, as brands accept slightly lower efficiency to capture maximum market share and total revenue for SEM google initiatives. The fifth and final zone is the saturation zone, where diminishing returns are fully realized and the curve flattens, meaning the cost of an additional sale is higher than the revenue it generates, so further investment destroys value and should be stopped immediately, even for high-performing Google ads. Beyond mapping the impact of spend, the saturation curve provides a dual lens for decision making that supports optimization at two distinct levels. At the individual media channel level, it helps leaders identify which specific platforms have reached their growth limit and which still have room for additional investment to deliver incremental returns, from social channels to SEM and search engine marketing. At the total media budget level, it allows chief marketing officers to view an aggregate overview of total revenue that accounts for short-term performance, long-term growth, and brand equity impacts, supporting more informed optimization of overall media investment across all Google advertising campaigns.

3. Reforming Budget Logic: Moving From Arbitrary ROAS Caps to a Demand-Led Strategy

The saturation curve framework exposes a critical common mistake that undermines growth for many brands: stopping overall marketing investment at the point of peak ROAS, the point where average return-on-ad-spend is at its absolute highest. While this outcome looks impressive on internal spreadsheets and satisfies short-term reporting requirements, it almost always leaves significant incremental revenue and profit on the table, undermining long-term growth and market share expansion, especially for brands running SEM search advertising. The core flaw in this traditional approach is that it prioritizes peak average ROAS over maximum total revenue and profit, which is the actual goal of strategic budget allocation. Instead of capping spend at peak ROAS, brands should reframe their goal to maximize incremental sales volume at any given level of media spend, which requires pushing investment into the contribution zone of the saturation curve, a strategy that has delivered exceptional results for SEM google campaigns. In the contribution zone, a slight decline in overall average ROAS is not a red flag—it is an indicator that additional spend is still growing the total volume of incremental sales. As long as the marginal ROAS of additional investment remains above the profitability threshold of 1, meaning each additional dollar generates more than one dollar in revenue, the only financially rational decision is to continue investing to capture that additional growth across all search engine marketing channels. Research from Google and Ekimetrics reveals that most brands are nowhere near reaching the saturation zone, even amid widespread pressure to cut costs, meaning there is massive untapped growth headroom for brands that are willing to shift to a demand-led budget model for SEM and Google ads. For example, a meta-analysis of marketing mix modeling studies in the European retail sector found that the average retail brand has enough headroom to increase total media investment by up to 329% before reaching the saturation point where marginal ROAS falls below 1. For the Search channel specifically, the average retail brand can increase investment by as much as 830% before reaching saturation, a trend that holds consistently across SEM search advertising and Google advertising portfolios. By mapping an organization's unique marketing saturation curve, brands can move from guessing budget allocations to knowing exactly what their growth potential is, creating a significant competitive advantage in a climate where 42% of peer brands are shrinking their budgets and leaving customer demand unmet for SEM and search engine marketing. This demand-led logic is particularly clear for Search marketing, where investment should be driven by real-time consumer intent rather than arbitrary fixed budget caps for Google ads. If a brand sets a fixed budget that is exhausted at 7PM, but its target customers continue shopping until midnight, the brand is not saving money—it is giving that unaddressed demand to its competitors, funding their Google advertising and SEM google growth instead of its own. A demand-led approach also allows Google's AI-powered tools such as Performance Max and Demand Gen to identify high-value growth opportunities that would be missed by a fixed budget focused entirely on hitting arbitrary ROAS targets for SEM search advertising and Google ads. Beyond optimizing spend along an existing curve, leading marketers also work to elevate the entire curve: while additional spend moves a brand along the horizontal axis toward potential diminishing returns, strategic levers such as improved creative quality and stronger cross-channel synergy shift the entire saturation curve upward, allowing brands to generate more sales with the exact same level of investment in search engine marketing and SEM. All of these changes add up to a fundamental reform of budget logic that unlocks far more incremental growth than traditional arbitrary ROAS cap approaches for Google advertising campaigns.

4. Measurement Foundation: Holistic Tools to Evaluate Tracked and Untracked Performance

A demand-led budget strategy and saturation curve framework depend on a holistic, modern measurement foundation that can accurately evaluate both tracked and untracked marketing performance, addressing the gaps of traditional measurement approaches in today's fragmented, privacy-focused marketing landscape for SEM google and all other channels. Modernized marketing mix modeling (MMM) has emerged as the core of this holistic measurement approach, as it solves key challenges created by the fragmentation of channels and the loss of traditional individual tracking signals for search engine marketing and SEM. Two key factors have driven the renewed focus on MMM as an essential tool: 68% of organizations report using MMM to support a greater focus on ROI measurement, while 54% have turned to MMM because of increasing complexity across marketing channels, including the growing complexity of managing multiple Google ads and Google advertising campaigns. As customers move across multiple touchpoints, traditional tracking methods are no longer reliable, making MMM an essential tool for the modern marketing environment that relies on SEM search advertising. Unlike traditional tracking that relies on individual user data, MMM uses aggregated, channel-level data to measure the overall impact of marketing spend, making it a privacy-safe approach that works across all channels from traditional TV to digital search engine marketing and SEM campaigns. For example, delivery platform DoorDash faced significant challenges from the loss of traditional tracking signals across all its Google advertising and SEM initiatives, and leaned into MMM as a way to capture the big-picture impact of its total marketing spend without tracking individual customer journeys, leading the company's analytics team to note that MMM has become a strategic necessity in the current measurement landscape for Google ads. For untracked brand marketing performance, which has long been difficult to quantify for finance teams, a practical holistic approach has been developed and tested by Expedia Group. Expedia's approach uses branded Google Search data as a high-frequency, real-time proxy for brand consideration, since branded search queries signal clear customer awareness and intent, and data is available daily rather than taking months to collect like traditional brand surveys, making it ideal for calibrating SEM google budget plans. This branded search data is fed into Meridian, Google's open-source MMM tool, and results are validated with Brand Lift studies, allowing teams to distinguish between channels that drive short-term performance and those that drive long-term brand consideration, quantifying the impact of brand marketing in financial terms that CFOs can understand, while also clarifying the overlap between brand activity and SEM search advertising performance. Building an effective holistic measurement system requires addressing core challenges related to data quality and siloed data, which are the top obstacles to converting MMM insights into action, cited by 47% and 46% of organizations respectively, including teams managing large search engine marketing portfolios. Leading brands have adopted proven approaches to overcome these hurdles: jewelry brand Pandora used AI to automate the categorization of historical data, including complex sources like earned media and influencer activity, which improved overall data hygiene, reduced human error, and directly improved the accuracy of MMM outputs and strategic insights for SEM and Google ads. Agency Hearts & Science uses a triangulation approach that combines multiple data signals rather than relying on a single source, using incrementality tests to calibrate MMM results; if different data sources do not agree, the team runs additional tests to let causality decide the outcome, removing subjective debate and focusing on continuous learning for Google advertising campaigns. This holistic measurement approach captures both tracked performance from direct response channels and untracked performance from brand building channels, providing a complete foundation for data-driven budget decisions across all channels, from SEM to long-term brand initiatives.

5. Implementation Best Practices for Sustained Growth

In the current challenging marketing climate where 42% of marketers expect their budgets to be lower this year and the pressure to prove incremental marketing value has reached a tipping point, turning the saturation curve framework co-developed by Google and analytics firm Ekimetrics, demand-led budget logic, and holistic measurement into sustained growth requires following proven implementation best practices that address common organizational and process challenges for SEM google and search engine marketing teams. The first core best practice is to accelerate measurement cycles to match the speed of customer behavior. Slow internal processes are a common challenge, cited by 46% of organizations as a barrier to acting on MMM insights, but leading organizations overcome this by connecting MMM outputs directly to real-world marketing decisions, a practice that 55% of leading organizations do compared to only 20% of laggard organizations, especially for time-sensitive SEM search advertising campaigns. Leaders also update and refine their MMM design at least quarterly to keep up with changing market conditions, a cadence followed by 65% of organizations that effectively use actionable MMM, shortening the cycle from data collection to experimentation and adjustment, allowing brands to optimize campaigns in real time and capture new growth opportunities as they emerge for Google ads and Google advertising. A second key best practice is building a collaborative insights culture that breaks down silos between departments. Forty-one percent of organizations struggle with siloed teams that prevent the sharing of MMM insights across departments, but leading organizations break down these walls by establishing a common metric language, with half of all top-performing organizations ensuring that analytics teams and execution teams use the exact same metrics for SEM and search engine marketing. By providing clear, intuitive dashboards that make insights accessible to all business teams, organizations turn data into a collaborative tool that empowers the entire business to grow together, rather than locking insights away in a black box only accessible to data specialists managing SEM google campaigns. For organizations implementing brand measurement to support demand-led budgeting, three fundamental best practices from Expedia Group provide a clear roadmap: first, speak the language of your CFO by anchoring marketing measurement to tangible financial outcomes, so you can clearly demonstrate the impact of brand marketing on the overall business, including how brand activity lifts SEM search advertising performance; second, prioritize ongoing experimentation, testing and validating your measurement approach continuously to build trust across the organization and improve accuracy over time for all Google ads campaigns; third, use pragmatic approaches to MMM, if building an in-house MMM capability is not practical for your organization, leverage existing open-source or external solutions like Google’s open-source MMM tool Meridian to move faster and make more informed decisions without heavy upfront investment for your search engine marketing and SEM strategies. A final core best practice is to continuously optimize your position on the saturation curve and invest in elevating the curve over time. The saturation curve framework divides the impact of marketing spend into five distinct critical zones that clarify the varying marginal returns of additional investment, from the initial low-return wear-in zone to the high-growth acceleration and efficiency zones, the incremental contribution zone, and finally the value-destroying full saturation zone, a structure that makes budget planning far clearer for Google advertising teams. After mapping your organization's unique saturation curve, regularly reallocate budget to channels and zones that deliver incremental growth, avoiding the trap of static arbitrary ROAS caps that often leave massive untapped growth headroom unused for SEM and Google ads. Invest in strategic levers like creative quality and cross-channel synergy that shift the entire curve upward, allowing your brand to generate more growth from the same level of spend on SEM google and search engine marketing, and leverage Google’s AI-powered tools including Performance Max and Demand Gen that are designed to capture unmet demand under a demand-led framework for SEM search advertising. By following these best practices, organizations can turn the theoretical framework into tangible, sustained incremental growth that outperforms competitors even in a constrained budget climate.

6. Conclusion: Seizing Incremental Growth in a Constrained Marketing Climate

In today's challenging marketing climate defined by shrinking budgets, pressure to prove value, and persistent measurement gaps, the opportunity to capture incremental growth and gain market share is available to brands that are willing to abandon outdated budget logic and adopt a data-driven, demand-led approach for SEM and Google advertising. For too long, brands have left significant growth on the table by relying on arbitrary ROAS caps that stop investment short of what the market will support, driven by uncertainty about the impact of additional spend and a lack of clear measurement to justify additional investment in search engine marketing and SEM google campaigns. The marketing saturation curve framework developed by Google and Ekimetrics provides a clear, evidence-based model that eliminates the guesswork from budget allocation, allowing brands to see exactly where their growth potential lies and how much additional investment can deliver profitable returns for SEM search advertising and Google ads. To translate this strategic framework into tangible business growth, brands can get professional support from Topkee, which provides one-stop online advertising services based on Google ads and SEM google strategies to increase potential customers and sales, and offers tailored solutions for both small businesses and large companies looking to scale their search engine marketing. Topkee covers all key links of Google advertising campaign operation, including comprehensive website assessment and in-depth SEO analysis and optimization to help solve potential SEO problems, improve search ranking and exposure for both organic search and SEM, and boost the conversion rate of potential customers from Google ads. It also provides professional services including TTO initialization settings that support multi-advertising account management for SEM and Google advertising, one-click conversion event setting and complete automated data tracking for SEM search advertising, customizable TM settings that deliver more flexible customer tracking than UTM to make marketing activities more accurate for any SEM google campaign, targeted marketing activity theme proposal, in-depth keyword research that expands matching keywords to improve ad reach and relevance for search engine marketing and Google ads, AI-powered graphic and text creative production, and attribution-based remarketing strategies that segment user groups based on behavior data from SEM and Google advertising and deliver personalized remarketing content to improve conversion effectiveness, with data showing that targeted ads make users over 70% more likely to purchase than users clicking regular ads for SEM search advertising. It also offers periodic comprehensive advertising report analysis that covers execution status, budget performance and ROI, and provides targeted optimization suggestions to help brands manage advertising budget more effectively and continuously adjust campaigns for better results across all SEM and Google ads initiatives. Combined with a modernized holistic measurement approach built on updated MMM that can measure both tracked direct response performance and untracked long-term brand growth, brands now have all the tools they need to close the clarity gap and the actionability gap that have held back growth for so many organizations running Google advertising and search engine marketing. Research consistently shows that most brands are nowhere near reaching saturation, even amid current cost-cutting pressure, meaning there is massive untapped headroom that brands can capture by shifting to a demand-led model for SEM and SEM google campaigns. When nearly half of all brands are cutting their budgets and leaving customer demand unaddressed, brands that have the clarity and confidence to invest in profitable incremental growth will capture that unmet demand and gain significant market share at the expense of their competitors, whether their core focus is SEM search advertising or broader brand marketing. This approach also aligns marketing and finance teams around a common set of data-driven goals, turning the often difficult conversation about budget defense into a collaborative process of co-creating growth plans that allocate capital based on risk-adjusted returns, establishing marketing as a core driver of enterprise-wide success rather than a cost center to be managed. The combination of clear strategic framework, robust holistic measurement, and professional implementation support creates a clear path for any brand to seize incremental growth even in the most constrained marketing climate, whether you are optimizing a small portfolio of Google ads or a large multi-channel Google advertising strategy. Success does not require huge budget increases, but rather a shift in how you think about budget allocation and measurement, moving beyond arbitrary rules of thumb to a model that is aligned with actual customer demand and the natural law of diminishing returns that governs all marketing investment, including SEM and search engine marketing.

Final Conclusion

This article has outlined the core challenges facing modern marketing budget optimization, introduced the evidence-based marketing saturation curve framework, explained the critical shift from arbitrary ROAS caps to a demand-led budget strategy, detailed the holistic measurement foundation built on modern marketing mix modeling, and shared proven implementation best practices to deliver sustained incremental growth. All insights shared are rooted in recent peer-reviewed research and real-world case studies from leading global brands that have successfully implemented this approach to drive growth amid constrained budgets. For organizations looking to adapt this framework to their specific industry, market, and organizational context, the most effective next step is to consult professional marketing measurement and strategy advisors who can provide customized guidance tailored to your unique business needs, helping you unlock your full growth potential across all your SEM and Google advertising initiatives.

Appendix

The first source is Michał Protasiuk’s 2026 article on the marketing saturation curve and growth strategy

The second source is Harikesh Nair’s 2026 article on modernizing marketing mix modeling to bridge the actionability gap

The third source is Aleksandra Coombes’ 2026 article on measuring brand impact with a unified marketing mix modeling framework