untidy, smelly, yellow smile, unshaved, sweaty, stink breath, ear wax, sweaty socks, hair on unpleasant place,too fat, too skinny,acne ...etc <<<<<<<<<<<Physical ...something that not normal will prevent you to be attractive for others sexes.
Too gloomy,too serious, too funny(joker), too smart, too stupid, too freaky.. etc.. <<<<< behavior/personality ... BAD habit and BAD personality will prevent you getting gf/bf.
For me
I'm Mr nice guy, friendly, have manner, and caring... but i can be untidy,big(hard,stubborn) head, not serious, and stupid(not trying to use my head lol) !..
so because i used to be very nice/soft to everyone, girls dislike it.
because sometime i can be a airhead or stupid(not listening), girls ignore me.
I have sweaty foots, so every time i say to peoples like: don't breath to much or you will smell my smelly foots xD....
That's what prevent me getting GF ....
but he .. that's how it work ..we have our positive and negative.
Always Pro and Cons