see the danger is that most guys are either in two groups; either they 1) don't have enough self esteem, or they feel inadequate for someone who is pretty and feel like they could never deserve her
and 2) there's the confident ones who feel they're worth anyone.
The problem is that 2 (whether boy or girl) is quite often a narcissist and narcissism is easily confusable with confidence. It's possible to not be narcissistic like this, but bc confidence is attractive, ppl end up getting with narcissists often, and this cycle keeps repeating
1 is usually hard to tell, they could really be anything and you learn once you get to know them. They could be narcissistic themselves, or they could be sweet.