The first question I ask when a founder pitches me a new startup idea is:
Show me the HABIT, the HASSLE and the HISTORY
HABIT: Show me the existing customer behavior / habit which clearly tells us there is demand.
HASSLE: Show me the existing hassle / hacky way they are solving for them that you can improve. Highlight the unmet need you “noticed” based on your customer interactions. This is also called “earned insights”
HISTORY: Show me evidence that you actually paid for this service / product or has personal history dealing with this problem (this indicates strong founder market fit)
(Especially observe the question: “how much will they pay today?”)
This is from Paul Graham
Note the emphasis on “problems you have yourself”