Why do I look for different things in girls than my friends?

Honestly, my friends call me a bit weird. They don't understand why i date the girls i do. I (not to toot my own horn) can actually get pretty good looking girls, yet i don't. Instead I blow her off and hang out with the girl that makes me smile and stuff, and most of the time that girl isnt really that attractive (not to be offensive) my friends dont really understand why, and personally i don't understand why either because we rate girls the same (sounds shallow but it still happens) and say stuff but yet i don't really want a girl like that. Can you tell me why that is? (maybe i answered this question without even noticing it but still maybe it is a psychological thing, or a esteem thing. I don't really know) Be critical, mean, honest, whatever you need to be. I just want some light shed upon my problem.(If it really is)