So I'm a 17 year old and can a girl answer this for me please?

So I'm 17 and like whenever I try talking to a hot girl they always act so stuck up but then I'll see a bummy looking guy with a hot girl? I'm not a bad looking guy like i wear like 500$ jeans and stuff alot of people say i look like Leonardo dicaprio but I just don't understand why they don't even give me the time of day but then they like ugly guys?