In my experience, a great customer isn’t just one that buys that your stuff. A great customer is one that also raises your game.
And how do they do that? Like any good relationship, it isn’t a laundry list, it’s more about chemistry. Something just clicks.
The other thing is, they don’t let you get away with second rate, and they’ll tell it to your face if you try.
A great customer wants you to be world class, and is willing to help you get there. Learn to spot them early, and then treat them like gold. Enough said.