I think it's been conflated with simply "having self-esteem". So many guys (and a few women), are just so meek and weird about flirting or even just having casual conversations with the opposite sex. Like they see themselves as a social burden, but they just have to approach and give weird compliments anyway.

Like, you've seen sorta fugly people with attractive partners, right? Or two not-so attractive people dating? Someone had to make a move, and those people had self-esteem / confidence.

Confidence isn't just reserved for the physically attractive. It's ok to value other aspects of yourself and derive your self-worth from that.

If you're bothering people who turned you down already, or you're too unaware to notice, then that's a different problem altogether. I've seen plenty of guys with zero confidence linger in a convo they thought was going somewhere.