This series started with a question from Lenworth Henry at Google Cloud, who works with early-stage founders on the Founders Advocates / Startup Ecosystem team. He asked how founders can figure out how much to build, how to price it, and how to make sure the numbers actually work. This is the final post in the three-part series. Post 1 on how to actually know what to build, and post 2 on the pricing trap most tech founders fall into, are worth reading first.
Here’s a pattern that shows up in early-stage founder conversations more often than almost any other.
The founder has a big idea. Real vision. They can articulate it well. They also know it’s going to be hard to build directly. The technology is complex, the customer education required is heavy, the sales cycle is long, or the market isn’t quite ready. So they arrive at what feels like a clever workaround.
They decide to build a smaller, simpler business first. One that can generate cash quickly, prove some capabilities, build a customer base, and then eventually fund or evolve into the real thing they want to build. It’s a very expensive mistake.
Why building A to fund B looks like a good idea
The logic is seductive because it seems to solve two problems at once.
The first problem is capital. Your real idea needs runway you don’t have. If you can build a smaller business that generates revenue faster, you can bootstrap your way to the resources you need. No dilution. No investor pressure. Just cash you earned yourself.
The second problem is validation. If your smaller business succeeds, you’ve proven you can execute. You’ve built customer relationships. You’ve built a brand. All of that becomes an asset you can carry into the bigger idea when the time comes.
On paper, that’s a clean argument. In practice, it almost never works, and the reason it doesn’t work is that you’ve quietly turned one risky bet into two.
The math actually works against you
To get to your real idea, business A has to succeed and you have to successfully transition to business B. That’s not one probability. That’s a joint probability, and joint probabilities compound the wrong way.
If business A has a 40% chance of succeeding well enough to fund business B (which is generous for an early-stage business), and business B has a 40% chance of succeeding given adequate funding, your combined odds are 16%. You’ve cut your chance of ending up where you actually want to be by more than half.
That’s the mathematical case. The strategic case is worse.
Because business A isn’t the business you actually want to build, you’ll be a mediocre operator of it. Not incompetent. Mediocre. Your heart won’t be in the work. Your attention will keep drifting to business B. You’ll under-invest in the parts of A that don’t map to B, which will be most of the parts.
Meanwhile, business B is sitting in your head, unbuilt, aging. The market conditions that made it look attractive shift. Competitors show up. The window narrows. By the time business A has generated enough cash to fund B, B might not be as interesting as it was when you started.
And here’s the specific mode of failure to watch for. Business A tends to become a comfort trap. It’s generating cash. It’s paying salaries. It’s real. Walking away from it to bet on B feels reckless even when B was the whole point. Founders in this position often end up running A forever, with B as a permanent “someday” that never arrives.
The alternative: build a small version of the big idea
The move that actually works is deceptively similar to the A-to-B strategy, but it produces completely different outcomes. Instead of building a different business to fund your real business, build a small, complete version of your real business directly.
A slice of the pie is a partial implementation of your vision. One feature. One workflow. One customer segment. It only works if the whole pie eventually gets built, because a slice on its own doesn’t stand up.
A small pie is a complete instance of the vision, scaled down. All the essential elements of the big idea are present. It just serves fewer customers, in a narrower market, with a simpler feature set. It’s a real business that would still be a real business even if it never grew.
Concrete example. Say you want to build security software for enterprises. Big vision. Complex. Long sales cycle. Requires deep integration with customer systems. You’re not going to sell it in month one.
The A-to-B mistake is to build a penetration testing business first. Sell pentests. Generate cash. Use the cash and the customer relationships to eventually fund the security software you actually wanted to build. That’s building A to fund B. The pentest business and the security software business are related but structurally different. Different sales motion, different pricing model, different unit economics. Success in one doesn’t cleanly transfer to the other.
The small-pie alternative is to build a monitoring system that installs quickly, surfaces security alerts, and lets customers resolve them manually. That’s a real security product. It’s a scaled-down version of the eventual vision (which might include automated remediation, deeper integrations, and full workflow coverage), but every customer who buys the monitoring system is a customer who could buy the fuller product later. The muscle you’re building is the exact muscle you need. The customer relationships are the exact relationships you’ll want. Success at the small scale directly proves the bigger scale.
That’s the difference. Same amount of caution about starting too big. Completely different odds of getting to where you’re trying to go.
Where this pattern shows up most
The A-to-B trap is not just an AI-founder problem, and once you see the pattern you start noticing it everywhere.
The most common version is the services company that plans to become a software company. Founder starts an agency or a consultancy to generate cash, with the idea that they’ll build software on the side and eventually pivot the business into a product company. It almost never happens. Agencies are structurally different from software companies. The economics are different. The team you build is different. The customer conversations are different. Founders who try to run both end up running an agency that has some half-built software on the shelf, and they run it until they retire.
The small-pie alternative for that founder is to build the software directly, even if it’s tiny. One workflow. Ten customers. Real revenue at real software margins. Then grow.
Another version is the founder who launches a lifestyle business to fund their startup ambitions. Newsletter, coaching practice, digital course. All fine businesses. None of them turn into a venture-scale company. The founder ends up with a decent living and no startup.
If your goal is a decent living, that’s a great outcome. If your goal was the startup, you built the wrong thing.
The pattern to watch for is any strategy where the plan requires you to succeed at one type of business well enough to then start a different type of business. That’s a compounding bet. Almost never the right move.
The diagnostic
There’s a specific question worth asking anytime you’re tempted by the A-to-B path.
Is the business I’m about to build a smaller version of the business I actually want, or is it a different business that I hope will fund it?
If the answer is “it’s a smaller version and every customer is a plausible customer for the fuller version,” you’re on the right path. Build it.
If the answer is “it’s a different business, but it uses similar skills and I think I can pivot later,” you’re headed into the trap. The pivot is much harder than it looks from where you’re standing now. Success at the different business will make the pivot feel more, not less, dangerous.
Build the small version of the thing you actually want. Even if it’s tiny. Even if it doesn’t look impressive on a pitch deck. Even if it’s harder than it would be to build something adjacent that generates cash faster.
The founders who get to their real vision are the ones who started building it, in some form, from day one. The founders who never get there are the ones who built a bridge business that turned into a destination they never meant to reach.
Your idea is the point. Start it small, but start it. Don’t build something else and hope to work your way over.