Christin just hit the nail on the head! Bad men are manipulative, calculative, well informed and in most cases, they do their homework well, even before approaching the lady. Also, another huge factor to this is when the lady is not fully matured or exposed, the figure they constantly see on the TV or read on magazines becomes their fantasy crush and whoever does not compliment such a fantasy has no chance in breaking through her heart.
But with time and maturity, a lot of decent women never consider such choices. In my university days, a lot of good guys were becoming something else just to fit into the "bad boy" dominated environment we were in And yet a few intelligent guys who were in fact "hibernating" were sort after by ladies from all corners. And then I realized another huge point which changed this mentality. Even in their "unexposed" phase of life, as a guy, be very good at ONE PARTICULAR THING! And the ladies who are attracted to guys with such a feature will come knocking at your door of interest! One final thing I want to say is, women are very complicated beings and it would be disaster if you tag them with a one way formula. One of my "good guy turned bad dude" friend regretted it, as even with his swag, his new and enticing charisma, his money and his language flows; the ladies weren't forth coming!
So, if you find a girl who wants to date someone similar to Usher or nelly or Eminem or any of such individuals, give her some space and look else where... In a few years time, you will marvel at her new taste of men!