Founder-market fit when your market is your old profession

Founder-market fit is one of those phrases investors use to mean “why you?” For a lawyer building legal tech, the answer seems obvious, and I’ve leaned on it myself: I sat in the chair, I know the work, I know the people. That’s real. But having spent years building for the profession I left, I’ve come to think the obvious answer is only half the story. The other half - the blind spots, the network that cuts both ways, the strange shift in how your old colleagues see you - is the part that decides whether the fit actually holds.

Your experience is a sample of one

The first trap is that your expertise is narrower than it feels. I trained and practised at large international firms, in real estate, at a particular level of seniority, in a particular decade. That gave me a deep and accurate picture of one slice of legal work. It did not give me a picture of how a litigation team runs, how a regional firm makes buying decisions, or what the work looks like for someone in legal operations who has never recorded a billable hour.

The danger is that deep knowledge of one slice feels like knowledge of the whole. You generalise from your own experience with a confidence you’d never accept from an outsider. And your memory is frozen at the point you left: the workflows, the tools, the pressures of that era. The profession kept moving after you walked out. Your mental model didn’t, unless you made it.

You were the user, never the buyer

Most lawyers who build for lawyers were users of legal technology, not buyers of it. I knew exactly what a fee-earner needed late on a completion day. I knew far less about how a firm’s IT, risk, procurement and management functions decide whether to spend money, or what a chief operating officer is actually measured on. Those people often matter more to whether you get bought than the fee-earner does.

The ex-lawyer’s instinct is to build brilliantly for the user and assume the purchase will follow. It frequently doesn’t. Part of founder-market fit is learning a side of your old profession you never saw from the inside, and being humble about the fact that you’re a newcomer there, however senior you once were.

The network cuts both ways

Your network is the most obvious advantage you have, and the one most likely to mislead you. Former colleagues will take your call. They’ll give you an hour, look at your prototype and say encouraging things. Some will become your first customers. All of that is genuinely valuable, and it’s also a poor source of signal.

People who like you are polite about your product. They agree to small pilots partly as a favour. They forgive things a stranger wouldn’t. So the early evidence you gather from your network is systematically flattering, and it’s easy to mistake goodwill for demand. The fix is to deliberately test with people who don’t know you and owe you nothing. Their indifference is the most honest feedback you’ll ever get.

There’s a quieter cost, too. A network is finite, and every awkward sales follow-up spends a little of it. It also tends to point you at firms just like the ones you came from, which quietly narrows your market to your own CV. Treat those relationships as something you’re borrowing against, not a resource that renews itself.

One of them, or a vendor?

The strangest shift is in identity. When you first leave, you’re still one of them - a lawyer who happens to be building something. That opens doors and earns you a hearing that outsiders rarely get. Then, at some point, you send a proposal with a price on it, and you become a vendor. The same people who swapped war stories with you over coffee now read your emails the way they read every other supplier’s.

Both identities carry baggage. As “one of them”, you’re trusted on insight, but you may be expected to give advice for free, and your product gets judged as though it were a favour between colleagues. As “a vendor”, you’re held at arm’s length, scrutinised on price and terms, and occasionally regarded as someone who couldn’t hack practice. Neither reaction is unreasonable. The mistake is pretending you can be one without the other. You can’t. You have to know which role you’re in, in each conversation, and let people see that you know.

Keep the fit honest

None of this means the lawyer-founder’s advantage is overstated. It means the advantage decays unless you maintain it. Go back to the desk regularly and watch people work, especially people in roles you never held. Spend real time with the buyers you never were. Treat your own experience as one useful data point, not the specification. And be honest with yourself about whether a former colleague’s yes is a market signal or a kindness.

Founder-market fit, for a lawyer building for lawyers, isn’t something you arrive with. You arrive with a head start and a set of assumptions that feel like expertise. The fit is what you build by testing those assumptions against people who don’t know you, in parts of the profession you never worked in, until you understand the market better than you ever understood the job. That’s the version worth having, and the only one that lasts.