Two market questions decide a lot of plans, and decks tend to answer the easy one loudly and the hard one not at all. The easy one is the size of the market. The hard one is why this company should exist now rather than five years ago or five years from now.
This article is one in a series. The series discusses the method we use to judge whether a business plan is fundable. We have developed a multipart weighted scorecard, based partly on research into best practices and partly on my experience in the startup and venture space: five startups, two exits, startup investing, and founding a startup accelerator. There will be one article for each scoring category, plus one on red flags.
There's a selfish reason for doing it in the open: we are building the methodology into a managed AI agent that evaluates plans against real investor decisions, and writing each part out is how we find where it's wrong. If you're raising funding for a startup, you get the rubric we would use to grade you. If you think we have weighted something badly, tell us. That's the most useful note we can get, and it's why we're laying the series out this way.
Market and timing carry real weight in our scorecard, and more of it than the product, because the size and shape of the opportunity set a ceiling the best execution can't lift. A great team in a market that can't generate returns is a tragedy we've all watched happen. But the weight is easy to misread, so I want to be precise about what we are actually grading: not the headline number. That distinction is the point of the next section.
The TAM trap
Almost every deck has a slide with a large number on it. The total addressable market, usually in the tens of billions, often sourced to an analyst report. The number is meant to reassure. It does the opposite for an experienced reader, because the way it was produced tells us more than the number itself.
The trap is the top-down market size. You take a giant industry figure, assume a small percentage of it, and present the result as your opportunity. "The global logistics market is 9 trillion dollars, and we only need 0.1 percent." That sentence is a tell. It says the founder reasoned from a number they found to a number they wanted, and the only honest thing in it is the word "only," which is doing a lot of quiet work to make a fantasy sound modest. I have never invested Series A money in a company with a top-down TAM.
What I look for instead is a market built from the bottom. Who specifically buys this, how many of them are there, what would each one plausibly pay, and what does that multiply to. The number that comes out is almost always smaller than the top-down figure and far more useful, because every input is something the founder can defend. A founder who says "there are roughly 30,000 firms like our first customer, they'd pay something like 12,000 dollars a year, that's a 360 million dollar market we could actually reach" has told me they understand their business. A founder leading with the 9 trillion has told me they understand PowerPoint and how to find an optimistic analyst.
So on market size we are not grading big versus small. We are grading bottom-up versus top-down, defended versus borrowed. That sets up the next distinction: what kind of market shape the plan is actually in.
Three shapes of market, and the one that fails a gate
Here is where I'll codify something that I have been treating as a judgment call, and flag it as the spot most in need of your scrutiny, because turning a feel into a category is exactly where a rubric can fool itself into false precision. To make that judgment legible, I'm breaking markets into three shapes.
For our purposes, every market falls into one of three shapes. Venture-scale: large enough, or growing fast enough, that a winning company could plausibly return a fund many times over. This is what venture money is for, and a plan that lands here clears the gate. Capped: a real market with a real ceiling, where even total dominance produces a good business but not a venture outcome. These companies are often excellent and should usually be funded another way; pitched to a venture investor at a venture valuation, the structure itself fails the gate, no matter how strong the rest of the plan is. And unclear: the market might be venture-scale or might be capped, and the plan hasn't done the work to tell which.
The unclear case is the most interesting and common. It is not an automatic fail, because genuine early markets are hard to size, and some of the best outcomes came from markets nobody could measure at the time. What we grade in the unclear case is whether the founder knows it's unclear and has a plan to resolve it, or whether they have papered over the uncertainty with a borrowed billion-dollar number. Honest uncertainty about a market's ceiling is a fundable position. Manufactured certainty is the thing we penalize at the gate. That distinction matters before we turn to timing.
Why now
Timing is the question decks fumble most on, and it accounts for half of this dimension. "Why now" asks what changed in the world that makes this the right moment for this company, and the payoff is whether the window is open long enough to win before it closes. A new technology became cheap enough. A regulation opened or closed a door. (Regulation-enabled businesses are a post unto themselves). A certain behavior crossed a threshold. The answer should point to a specific shift with a date attached, not to a general sense that the space is heating up.
The reason this matters is that a startup is a bet against incumbents and against the dozen other founders having the same idea this quarter. A good "why now" explains why the opportunity is open at all, and why it won't stay open long enough for a slower, larger competitor to take it. That is the payoff: timing turns a good idea into a reachable one. A plan with no "why now," or one whose answer is "the market is growing," has skipped the question that separates a timely company from one that is early, late, or simply one of many. Being too early is a way to be right and still lose.
Current view, subject to change
The TAM trap I am sure about. I have never once seen a top-down market slide that improved my opinion of a plan, and I have seen many that sank it. Bottom-up or nothing, because the payoff is credibility: it shows the founder can defend the market they are actually trying to win.
The three-shapes model is the part I'm holding loosely on purpose. Sorting markets into venture-scale, capped, and unclear imposes a clean taxonomy on something that is genuinely a spectrum, and the capped-equals-gate rule could wrongly kill a plan whose ceiling is higher than it first looks, which happens more often than our tidy frameworks admit. As we run real plans through the agent, I'll be watching whether the markets we label capped actually stayed capped. If the ones we gated turn out to have broken through their ceilings at a rate that embarrasses the rule, the taxonomy is too confident, and I'll soften the gate into a flag. That would change my mind.
What I hold most firmly: the size of the number on the slide is close to meaningless, and how the number was built is close to everything. That is the thread running through the whole argument.
Regards,
Charles Stack
Founder, Coworkers.Global