Nobody is perfect, and you don't need a co-founder who is just like you. But some patterns predict trouble so reliably that you should walk away, or at least slow down.
Serious red flags
- Asks for a large share of equity before doing any work.
- Refuses vesting, or anything in writing.
- Inconsistent stories about past jobs or companies.
- Blames everyone else for every past failure.
- Disappears for days without a word, then acts like nothing happened.
- Lies, even about small things.
- Treats waiters, juniors or customers badly.
- Wants the title and the credit, but not the boring work.
Yellow flags: talk about them
- Very different ambitions (a lifestyle business vs. raising venture capital).
- Can only work part-time for a long, open-ended period.
- Very different appetite for risk with money.
- Different views on who should lead.
- Another side project they won't give up.
Yellow flags are not deal breakers. They're topics for an honest conversation and clear terms in your agreement.
Not red flags
- A different working rhythm (morning vs. night).
- Disagreeing with you, as long as it's respectful and leads to a decision.
- Saying 'I don't know' instead of making something up.
Call two people who worked with them before. Ask: 'Would you work with them again?' Hesitation tells you a lot.