The Glossy Slide Deck Lie
Aug 5, 2025
Every startup pitch deck opens with the same theatrical flourish: a slide showing astronomical numbers, planetary-scale markets, trillion-dollar opportunities. “$500 billion TAM,” the founder declares with practiced confidence. “We only need to capture 0.01% to build a unicorn.” The investors nod sagely, the narrative momentum builds, and everyone pretends this mathematical masturbation means something. Your gut knows better—this isn’t analysis, it’s anesthesia. A numbing agent designed to bypass critical thinking and mainline directly into greed glands.
TAM, SAM, SOM—the holy trinity of market sizing acronyms, each more divorced from reality than the last. They parade across pitch decks like precision instruments when they’re actually psychological props. We’re not measuring opportunity; we’re measuring the density of collective delusion. The bigger the TAM, the bigger the lie everyone agrees to believe. It’s not market analysis—it’s mass hypnosis dressed in Excel.
The real tell is how quickly founders skip past the mechanics to the fantasy. They don’t explain how they’ll capture market share; they just multiply big numbers by small percentages and call it destiny. This isn’t strategy—it’s numerology. And everyone in the room knows it, but the dance continues because admitting the truth would puncture the bubble everyone’s invested in inflating.
What the Acronyms Actually Mean (and Why It Doesn’t Matter)
Let’s decode this carnival of acronyms. TAM—Total Addressable Market—represents the theoretical revenue if you owned every possible customer in your category, if geography didn’t exist, if competitors vanished, if regulation disappeared. It’s the market-sizing equivalent of asking “What if everyone on Earth bought my product twice?” Useful for impressing naive investors, useless for building actual businesses.
SAM—Serviceable Addressable Market—pretends to be more realistic. It’s TAM with a geographic haircut, maybe some demographic trimming. “We’ll only target English-speaking countries with GDP per capita above $30,000.” Still fantasy, just with smaller numbers. SAM is TAM’s slightly less delusional cousin, the one who only claims they could’ve been a rockstar instead of insisting they already are one.
SOM—Serviceable Obtainable Market—is where reality theoretically intrudes. What you can actually capture with your current resources, team, and model. But even SOM gets inflated because it’s still based on assumptions about market share that ignore the brutal truth: most startups capture nothing. They die in the gap between PowerPoint and product-market fit. The deflection works because everyone focuses on the TAM moonshot while ignoring that the company can’t even reach the SOM stepladder.
Diogenes Would’ve Laughed at the TAM Slide
Diogenes, that magnificent bastard who lived in a barrel and mocked Plato, would have had a field day with modern pitch decks. He famously wandered Athens with a lamp in broad daylight, claiming to search for an honest man. In today’s venture capital offices, he’d need a floodlight and a hazmat suit. The TAM slide would send him into paroxysms of cynical laughter—here’s humanity, still dressing up greed as wisdom, still mistaking big numbers for big truths.
Picture Diogenes in a Sand Hill Road conference room, watching a 25-year-old founder claim their dating app for left-handed dentists addresses a $50 billion market. He’d probably start masturbating, just like he did in the Athens marketplace, to demonstrate that at least one person in the room was engaged in honest self-gratification. The TAM obsession is modern hubris wearing a spreadsheet costume, the same emperor with new clothes, or rather, no clothes but better PowerPoint transitions.
What Diogenes understood—and what TAM theatrics obscure—is that truth lies in the specific, not the general. When Alexander the Great asked what he could do for Diogenes, the philosopher replied, “Stand out of my sunlight.” He wanted the one real thing Alexander was blocking, not the empire Alexander could theoretically offer. TAM is all empire, no sunlight. It’s the promise of everything that delivers nothing, because it starts with abstraction instead of reality.
The Cognitive Illusion of TAM: Enter Kahneman
Daniel Kahneman spent decades documenting how our brains systematically fail us, and the TAM phenomenon is a masterclass in cognitive exploitation . Our System 1 thinking—fast, intuitive, emotional—loves big numbers. They trigger something primal: big equals safe, big equals important, big equals worth paying attention to TAM works not because it informs but because it excites. It bypasses analysis and hits directly at the feeling of potential.
The framing effect that Kahneman identified explains why TAM slides are so seductive Present the same startup opportunity as “pursuing a $500 billion market” versus “competing for 1,000 initial customers in San Francisco,” and watch how differently investors respond. The information might be identical—the startup still needs those first 1,000 customers—but the framing transforms perception. Big TAM numbers create a cognitive anchor that makes everything else seem achievable by comparison.
This isn’t accidental. Founders and their advisors have internalized that investors are buying dreams, not spreadsheets. So they lead with the biggest possible dream, knowing that Kahneman’s availability heuristic will do the rest Once that trillion-dollar number is lodged in an investor’s mind, it becomes the reference point. The actual business—with its mundane customer acquisition costs and brutal churn rates—seems like mere implementation details. The dream becomes more real than the trench warfare required to build something.
Christensen’s Warning: Wrong Market, Wrong Game
Clayton Christensen’s disruption theory exposed a fundamental flaw in how we think about markets: they’re not fixed entities waiting to be carved up like turkeys. They’re dynamic systems that reshape themselves around new behaviors and capabilities. Yet every TAM calculation assumes markets are static—that the $500 billion market for taxis remains a $500 billion market when ridesharing arrives, just with different players. This isn’t just wrong; it’s catastrophically misleading.
Christensen showed that disruptive innovations often create new markets rather than capturing existing ones. The personal computer didn’t capture mainframe market share—it created entirely new use cases. Smartphones didn’t divide the existing phone market—they absorbed cameras, music players, maps, and dozen other categories into a new paradigm. But TAM slides pretend markets are zero-sum games with fixed boundaries, missing that true innovation redraw the maps entirely.
The contradiction at the heart of most pitch decks is stark: they claim to be disruptive while using market-sizing frameworks that assume no disruption. It’s like planning a revolution using the king’s org chart. The TAM model is inherently conservative, built on backward-looking data about existing consumption patterns. But the startup claims to be forward-looking, behavior-changing, paradigm-shifting. One of these stories is false, and since the startup hasn’t shipped yet, guess which one.
Real Markets Are Psychological Terrain
Markets aren’t geographic regions or demographic segments—they’re psychological territories that expand and contract based on belief, fear, status, and story. Your TAM can evaporate overnight when a competitor’s scandal taints the entire category. Your SAM can explode during a crisis that suddenly makes your solution essential. Trying to size these fluid, reactive systems like they’re static inventories isn’t just wrong—it’s delusional.
Real markets move like weather systems, shaped by invisible pressures and sudden state changes. A viral TikTok creates a market that didn’t exist yesterday. A regulatory change destroys a market that seemed eternal. The pandemic turned billion-dollar markets into zeroes (business travel, conference venues) while creating trillion-dollar markets from nothing (remote work tools, delivery everything). Any TAM calculated in 2019 became toilet paper by April 2020.
Markets aren’t served—they’re summoned. They emerge from the intersection of capability, narrative, and timing. The iPhone didn’t address a pre-existing “smartphone market.” It created a new psychological space where a $1,000 pocket computer became essential to human identity. No TAM calculation predicted that because TAM can only see what already exists. It’s a rearview mirror pretending to be a telescope.
From Dream to Execution: Why SOM Is All That Matters
Strip away the TAM theater and SAM sophistication, and you’re left with SOM—the only number that touches reality. SOM is where theory meets thermodynamics, where slideware meets software, where promises meet P&L. It’s not about theoretical billions but actual thousands: How many customers can you reach this quarter? How many will pay? How many will stay? This is the knife fight in a phone booth that determines survival.
But SOM is unsexy. It’s small numbers, grinding progress, linear growth in a world that fetishizes exponential curves. So founders minimize it, investors ignore it, and everyone focuses on the TAM fantasy because it’s more fun to dream about billions than fight for hundreds. The irony is that every massive company started with tiny SOM—Facebook with Harvard students, Amazon with book buyers, Google with academics. They won their beachheads before they conquered continents.
The difference between VC delusion and bootstrapped survival is the difference between TAM obsession and SOM focus. Bootstrapped founders can’t afford TAM fantasies—they need customers tomorrow to make payroll. So they obsess over their serviceable obtainable market with the intensity of someone whose survival depends on it, because it does. They build from reality up, not from fantasy down. And paradoxically, they’re the ones who often end up capturing those theoretical TAMs—not because they aimed for them, but because they built something real first.
The Beachhead Is Everything
Diogenes would approve of this conclusion: reject the illusion, embrace the real. TAM is the dream, SOM is the street fight, and only one of them matters. Most market narratives aren’t about opportunity—they’re about anesthesia. They exist to numb you to the brutal reality of how small your actual beachhead is, how few customers you can actually reach, how little market power you actually wield.
But that beachhead is everything. It’s the Normandy from which empires are built or disasters unfold. Every market revolution started with someone owning a tiny, specific, unsexy corner of reality. Not the theoretical TAM billions, not the aspirational SAM millions, but the actual SOM hundreds or thousands who needed something specific and were willing to pay for it. That’s where revolutions are born—not in boardrooms parsing acronyms, not in pitch decks promising billions, but in the dirty, tiny corner of reality you can actually own.
The TAM slide is a comfort blanket for people who can’t face the discomfort of starting small. It’s the participation trophy of market analysis—everyone gets a big number, everyone feels important, everyone avoids the harsh truth that 99% of startups capture 0% of their TAM because they never figured out how to capture their first hundred customers. The real entrepreneurs are in the trenches, fighting for SOM, building from proof instead of projection.
And if you’re not building from there—from the small, specific, serviceable reality you can actually touch, you’re not building at all. You’re just decorating slides, multiplying fantasies, and pretending that big numbers on a screen translate to customers in the world. They don’t. They never have. The market doesn’t care about your TAM. It cares about whether you can solve one real problem for one real customer, then do it again, and again, until the beachhead becomes a continent. Everything else is just expensive fiction.
