Most B2B proof-of-concept projects fail not because the technology doesn't work, but because no one validated whether the client was willing to bear the internal cost of solving the problem they just discovered.

Your POC worked perfectly. The technology performed. The data confirmed your hypothesis. The client nodded along in the final presentation.

And then nothing happened.

If this sounds familiar, you're not alone. After working with dozens of B2B startups navigating enterprise sales cycles, I've observed a pattern so consistent it deserves a name: the Successful Failure.

The POC technically succeeds. The commercial outcome fails. And founders are left wondering what went wrong.

Here's what went wrong: you validated the wrong thing.

A colleague recently shared notes from a roundtable in Paris bringing together VCs, Operating Partners, and key players from the French startup ecosystem. The conversation, by all accounts, was sophisticated. Concrete ROI metrics. Honest acknowledgments that "capital alone isn't enough." Thoughtful discussion of AI's impact on productivity and talent.

Reading through the summary, I was struck not by what was discussed, but by what wasn't.

One question was conspicuously absent:

If I had to start a VC or Operating Partner function from scratch today, knowing what I know and accounting for the three-year trajectory, what would I fundamentally do differently?

Instead, the discussion centred on incremental improvements to existing models. Adding GPT wrappers to knowledge bases. Thinking about AI for network matching. Debating batch formats versus continuous intake.

This isn't a criticism of that particular conversation. It's representative of where most of the ecosystem stands: mature enough for sophisticated execution discussions, not yet ready for uncomfortable structural questions.

This article is an attempt to ask those questions. Consider it food for thought.