I think Women (and Men), don't really know what they want until they get older. (Generally speaking)
Women may confuse the bad attitude, nonchalant, big ego of a bad boy...with confidence. They also like a bit of a "passionate relationship"
Women may also want someone to 'take control', and nice guys may just respect women too much.
I think these 'qualities" of a bad boy become less important as women get more mature.
Just a couple of thoughts
For those of you who find this thread interesting... you should read up on Sociobiology. There are some good books that explain some of the apparent contradictions in female behaviour. I read a book called 'Sperm Wars' years ago and it gave me an interesting perspective. I've always been a romantic person (still am - it's like herpes it never goes away

). But the fact is that infidelity is built into the system.
Women are attracted to 'player genes' because they're successful. However they're also attracted to stability because they need a reliable partner to provide for their children. The human female is, I believe, the only female mammal that can conceal her peak ovulation period. Every other species of female advertises distinctly when they are ready to ovulate.
The reason is so that women can consciously or unconsciously select the genes they most prefer. Having a solid, reliable mate to raise your kids... who doesn't realize that they're actually the 'pool boy's' kids is the genetic optimum.
Of course there's lots of countervailing factors and fidelity is prized and reinforced strongly by internal motivation as well as social sanctions. Men shouldn't play around on their wives... and women shouldn't mess around behind their husband's backs right? Right. And although both behaviours are bad... it's worse if the women cheats. Why? The old 'double standard' right? Here's why. It's biology. The reason it's worse is because a woman can never be tricked into raising offspring that aren't her own when she thinks they are. A man can. That's the bottom line. From an evolutionary standpoint, that's suicide. It's worse than personal suicide, it's genetic suicide. If you're a man, you've just forfeited all your nestbuilding and energy investment in rearing some other man's children. It's bad for a woman too... because she doesn't want you investing your energy and resources into some other woman's offspring. That's not good for her own babies.. but it's not as dire of a situation.
It's all biology. No, it's not very romantic but it does explain some things at the root level. Helps weed through the 'paradox' and mystery that surrounds relationships between the sexes and the puzzling notion of monogamy, what women want, what women say they want and why there seems to be so much ambivalence on their end. They're confusing to us men... they are designed to be that way.
I've noticed how women go through stages and prefer stability as they get older... I think everyone sees that. Childrearing changes a lot.. I've also noticed how many women lose interest in the men they're married too once they fill their lives with children. It doesn't have to be that way... but it helps to understand the biological context in which we live. If you're going to have a mate - you better have a damn good friendship as well because friendship engenders loyalty better than almost anything outside of a direct genetic tie.