Why Signals, Not Spreadsheets, Should Guide Your Next GTM Move

This informal CPD article, ‘Why Signals, Not Spreadsheets, Should Guide Your Next GTM Move’, was provided by Yash Mulik, Product Business Analyst at MarketSizer, an organisation which provides professional training in market sizing and account prioritisation, equipping businesses with the skills to optimise customer acquisition, expansion, and retention strategies.

Introduction

Most go-to-market (GTM) strategies begin with a spreadsheet

Rows filled with industries, regions, and account tiers. Formulas estimating Total Addressable Market (TAM), Serviceable Addressable Market (SAM), and Serviceable Obtainable Market (SOM). It’s clean. It’s structured. And it often looks great in a boardroom presentation.

But here’s the catch: by the time that spreadsheet informs your GTM execution, the data is stale. It doesn’t reveal who just requested a demo from your competitor. It doesn’t show who hired a new RevOps lead. And it definitely won’t surface accounts quietly browsing your pricing page again.

For fast-moving B2B SaaS companies operating in volatile markets, traditional market sizing practices fall short. Static models built on historical assumptions can’t keep pace with shifting demand, emerging competitors, or evolving buyer behaviour.

What’s needed is a new approach—one rooted not in hypothetical reach but in observable signals.

What Do We Mean by “Signals”?

A signal is a real-world indicator that an account may be ready to buy, churn, or expand. Think of it as evidence and not guesswork.

Here’s how they break down for GTM teams:

1. Behavioural Signals
These are actions that indicate interest. Examples include repeat visits to your pricing page, requesting a product demo, or engaging with thought leadership content.

As the Cluetrain Manifesto famously said, “Markets are conversations”, and behavioral signals are your buyer’s side of that conversation.

2. Lifecycle Signals
These relate to where an account sits in its customer journey: nearing renewal, stuck in onboarding, or showing drops in product usage. Timing is critical, and lifecycle signals help prioritise outreach when it matters most.

3. Competitive Signals
These reflect shifts in vendor preference. They might come from a review platform feedback mentioning migration pain, or job listings hinting at platform change. Tracking these can give you a leg up on competitors before a deal is even opened.

4. Organisational Signals
Signals like funding rounds, hiring surges in GTM roles, or regional expansion plans often precede investment in new tools and services.

From Signals to Market Sizing

The leap forward is applying these signals not just to individual accounts but to segment and size your entire market.

That’s the foundation of signal-based market sizing.

Traditional TAM/SAM/SOM models assign a theoretical ceiling based on firmographics and industry data. But signal-based sizing treats your market as a dynamic ecosystem. Instead of asking “How many companies fit our profile?”, you ask, “Where is real demand emerging right now?”

This allows SaaS teams to evolve market sizing from passive estimates to active, evidence-based motion plans.

Let’s Make It Concrete: Leveraging Buyer Intent Data in B2B SaaS

Consider a B2B SaaS company offering an issue tracking and project management solution, aiming to target engineering teams in rapidly growing startups. Instead of broadly targeting all product teams, they focused on startups actively adopting modern developer platforms and collaboration tools.

By monitoring public signals such as technology stack changes, hiring for engineering leadership, and activity on developer forums, they dynamically refined their target market to focus on companies likely to engage.

This approach helped them maintain product focus while expanding adoption among fast-scaling startups that fit their ideal customer profile. Signal-based market sizing allowed them to focus on real, in-market opportunities—saving time and increasing conversion efficiency.

Supporting this strategy, a study by Dreamdata revealed that B2B SaaS companies integrating G2 Buyer Intent data into their go-to-market strategies saw benefits. Specifically, deals influenced by platform intent signals were found to be twice as large in value compared to those without such signals. This underscores the effectiveness of leveraging buyer intent data to identify and prioritize high-value opportunities.

cpd-MarketSizer-Signal-based-market-sizing
Signal-based market sizing

Why This Matters Now

In today’s market, B2B teams are asked to do more with less.

Spending scrutiny is up. Growth expectations haven’t faded. And efficiency has overtaken expansion as the top priority for many GTM leaders.

Static TAM decks no longer cut it.

Boards want evidence: which segments are warming up? Which accounts are showing intent? Where are churn signals emerging?

Signal-based market sizing helps GTM teams:

  • Prioritise accounts based on observed behavior, not assumed fit
  • Forecast growth grounded in live data, not past reports
  • Spot emerging segments and test them faster
  • Align marketing, sales, and customer success around shared, signal-backed targets

What to Watch Out For: Limitations of Signal-Based Market Sizing

While signal-based market sizing offers a smarter, faster way to align with demand, it’s not without its challenges.

1. Signal Blind Spots:
 Not all industries or regions generate reliable digital signals. Companies operating in low-tech verticals or stealth modes may not surface on your radar even if they’re high-potential accounts.

2. Data Noise vs. Real Intent:
 Not every click or trial equals intent. Without proper scoring models and validation, teams risk chasing the wrong leads or misreading weak signals as strong ones.

3. Tooling & Resourcing Gaps:
 Operationalizing this approach requires integrated CRMs, intent data platforms, and enrichment tools something early-stage teams may lack.

4. Over-Prioritizing the “Now”:
 Signals reflect current momentum, but not always long-term potential. There’s a risk of ignoring high-fit accounts simply because they’re not signalling today.

5. Cross-Team Misalignment:
 Sales, marketing, and RevOps may interpret signals differently. Without shared definitions and clear play books, even the best signals can create confusion.

Signal-based sizing is not a silver bullet. It’s a lens, one that’s powerful when used correctly, but incomplete without context, strategy, and alignment.

Best Practices for Getting Started

  • Integrate intent data early: Whether from third-party platforms or your own CRM, start collecting signal layers and reviewing them regularly.
  • Revisit ICP quarterly: As segments evolve, your Ideal Customer Profile should too. Factor in new buying signals, not just firmographics.
  • Visualise your SOM weekly: SOM is your “short list” accounts that are actively buying or primed to switch. Keep it updated and visible to GTM teams.
  • Use signal scoring: Not all signals are created equal. Create weights for urgency, frequency, and value to inform prioritisation.
  • Educate your organization: From product to leadership, help everyone understand why signal-led sizing improves decision-making across the board.

Final Thought

Spreadsheets still have a role. But if they’re your only tool for market sizing, you’re flying blind in today’s fast-moving landscape.

Signal-based market sizing challenges you to think beyond theoretical potential and start grounding your GTM moves in live demand.

So take a moment to reflect and ask yourself:

  • Do your current market numbers reflect now, or last year?
  • Can your GTM team clearly see who’s ready to engage today?
  • Are you acting on assumptions or on actual signals?

Because in today’s market, success doesn’t go to the teams with the biggest TAM on a slideIt goes to the ones who spot demand early and move faster than the rest.

We hope this article was helpful. For more information from MarketSizer, please visit their CPD Member Directory page. Alternatively, you can go to the CPD Industry Hubs for more articles, courses and events relevant to your Continuing Professional Development requirements.

References

  • Cluetrain Manifesto – Levin, Locke, Searls, and Weinberger (1999): “Markets are conversations.” https://ubereye.wordpress.com/wp-content/uploads/2009/04/the-cluetrain-manifesto.pdf
  • Dreamdata (2024) B2B Go-To-Market Benchmarks 2022. https://dreamdata.io/blog/b2b-go-to-market-benchmarks-2022
  • McKinsey & Company (2022) The New B2B Growth Equation. https://www.mckinsey.com/capabilities/growth-marketing-and-sales/our-insights/the-new-b2b-growth-equation?
  • Slideworks (2024) How to Create Market Sizing Slides: TAM, SAM & SOM. https://slideworks.io/resources/market-sizing-slides-tam-sam-som-examples