One of the top factors that kills a woman's attraction for a man very quickly is him feeling like he is not enough. Being enough means that you don't need anything outside of yourself to make you happy or feel good about yourself-you derive your sense of self esteem from within.

When you feel like you aren't enough you search for things to compensate for your lack of feeling naturally attractive. You buy nice cars in order to get women. You workout and get into great shape JUST to get women. You buy drinks for women JUST to get them to talk to you. And you get into state JUST to get the girl to like you.