Product / market fit
BlocksEverything. This is the only true gate on the map.
A buyer you can name, a problem they already spend money or hours on, and a pitch you have heard repeated back to you in their words. Not a hypothesis you like. Evidence you got from talking to people who could pay.
Every step to the right will run beautifully and produce nothing. You will spend your best names learning what ten customer conversations would have told you in a week, and burnt lists do not grow back.