What do you like in the people you like?

I’m not talking about a list of adjectives, “oh, they’re nice and and thoughtful and caring…” because we all are. And we’re all less-than-nice and selfish and uncaring, too, at different times, to different people.
It’s not really about the niceness, the smartness, the funniness. Because so many people are those things. But that’s what we say, anyway. “Oh I like them, they’re really sweet.”
What is it that makes us like that? And then turn around and think someone else is too sweet, and someone else not sweet enough?

What is it that gives you that initial gut-feeling about someone? What is it that keeps you coming back to them? Or determined to avoid them?
We’re not just broad adjectives… so what are we to each other? And how do you describe that without those broad adjectives?