paul graham said "find 10 users who love you." but he never defined love.
i think he kept it intuitive on purpose, sort of open-ended for founders to figure out how to make users fall deeply in love with their product in different ways.
my definition of user love is they pay you, and they use you.
to verify this, ask for something that costs them something:
1. can we get 30 mins on your calendar for our next release?
2. here's a refundable deposit into the private beta, are you in?
3. can you name three people in your role we should talk to?
if you're not getting an instant "yes" something's not clicking. figure that out, fix it, and repeat this exercise. this loop will take you to pmf.