Build Just Enough: Why Founders Should Sell While They Ship

By Scott Henderson, Managing Principal, NMotion powered by gener8tor

If there’s one message we hammer home to founders over and over again, it’s this: More people fail by building too much too early than by selling too soon.

In other words, build just enough. 

Build just enough to prove there’s someone willing to pay for it. Build just enough to test the assumptions that could kill your business before it even starts.

Driving Two Horses Forward in Tandem

If you think of yourself as a farmer driving a team of two yoked horses, you start to understand this approach. One of the horses is Proof of Concept and the other is Proof of Customers.

To plow the field, you can’t just drive one horse forward. That’s unfortunately what some founders do by spending almost all their time focused on building the product out into a robust solution without ever trying to sell it to their target customers. 

Conversely, you can’t spend all your time selling to customers without ever delivering on your promises. They will eventually go elsewhere to someone who can. 

What works is the founder driving the Proof of Concept forward enough to then test against the customer’s needs. As you keep building enough of a solution to prove enough of customer desire to take action, you will find your startup making the progress you need. 

Selling Is Learning

We get it—selling can feel uncomfortable. You didn’t start a company to cold-call strangers. But if you’re a founder, and you haven’t yet sold $1M worth of product, you need to be in the trenches selling. Not just because it makes you money, but because it makes you smarter.

Sales isn’t about pitching features. It’s about listening for pain, hearing objections, and figuring out what words actually unlock interest. It’s about learning what people care about enough to act on. It’s a kind of learning you can’t outsource as a founder.

You’ll never be closer to the truth of your business than when you’re face-to-face (or Zoom-to-Zoom) with a real customer who is deciding whether or not to pay.

Start With Assumptions

Every startup is built on assumptions. That the problem is real. That people care enough to pay. That they’ll use it the way you think they will.

The faster you test those assumptions, the better. Because here’s the truth: you’re wrong about something—you just don’t know which part yet.

So how do you test an assumption? I recommend reading the Minimal Viable Testing Process blog post from First Round and focus your attention on what it says about key critical assumptions and the Atomic Unit Test.

1. Identify it clearly. What is the key critical assumption you’re betting the business on?

2. Attach a metric. What would prove it right—or wrong?

3. Set a timeline. We like tight two-week sprints.

4. Design the test. What action can you take right now to validate or disprove it?

You’re not trying to prove your idea. You’re trying to disprove it. That’s the scientific method. If the idea survives real scrutiny—great. But don’t spend months building something only to realize no one ever wanted it in the first place.

Key Critical Assumption

Take Uber, for example. One core assumption: that people would get into a stranger’s car. If that assumption had failed, there’d be no Uber. No Lyft. Game over.

Every founder has their own version of that atomic unit test. Maybe it’s whether campground owners are willing to automate bookings. Maybe it’s whether hot cocoa buyers prioritize taste over convenience. Whatever it is, find the one assumption that, if false, breaks your business. Then go test it.

Make Your Sprint Count

Once you’ve got your key assumption, break it down into a focused, two-week sprint. Something like:

• Assumption: People are willing to buy this solution now.

• Metric for success: 5 sales demos booked.

• Tasks: Build a prospect list. Draft and send outreach emails. Follow up. Schedule demos.

You don’t need 10 priorities. You need one or two that matter. Put your head down for two weeks and run fast. Then regroup and learn.

Action Talks. Everything Else Walks.

Founders love to ask what customers might do. That’s a trap.

The better question is: What have they already done?

• Did they give you their email?

• Did they show up to a demo?

• Did they put a deposit down?

Future intentions are cheap. Past actions are honest. That’s why we say: there’s no traction without action.

Even if they’re just taking a small step—signing a letter of intent, joining a waitlist, attending a test—they’re signaling interest with real behavior. That’s the kind of data you can build on.

Final Thought: Everything Should Point to Revenue

Whether you’re raising venture capital or bootstrapping from scratch, your energy should flow in one direction: toward revenue. Not swag. Not vanity metrics. Not “building in stealth.”

Your job is to climb the traction triangle—step by step—from customer interest to customer cash. And if the top feels out of reach? Start one level down and take real action from there.

Your idea doesn’t become a business until someone buys.

So go sell. Learn something. Prove something. And build only what’s worth building.