A prototype helps a lot. Traction helps too, but we tried not to get fooled by graphs. In fact, I always ask the other interviewers "would we fund this compan

A prototype helps a lot. Traction helps too, but we tried not to get fooled by graphs. In fact, I always ask the other interviewers "would we fund this company if they had no traction at all?" To fund a company with nothing built and no users, we have to believe 1) the idea is great and 2) the team is unstoppable.