Let me just say that I love a nice guy.  I think you guys get a bad rap and get overlooked just as much as the nice girl does.  (Sometimes you nice guys overlook the nice girl too).  But there are a few qualities that the bad boys have that many women are attracted to and that most 'nice guys' just don't have or display I should say.  

No woman wants a bitch. What I mean by that is, no woman wants a man that will just bend to her every whim with no fight, no resistance, no debate.  Women like a man that has a backbone.  That has his own ideas, goals, interests and is strong enough and open enough to share them with her.  Women like a man who has his own principles and who can stand up for them when the time calls for it.  Sometimes women need to be told when they are going too far.  I don't care what she says.  

There is something very sexy about a man who can stand on his own two feet, command attention in a crowded room, and is secure enough in who he is to let you know who he is. I think what many 'nice guys' do is let the woman take the lead.  They don't want to appear as dominating, disrespectful of her ideas, or inattentive to her her needs so they often just, I hate to say it this way, bow down.  That's something that your 'bad boy'/jerk won't do. Nice guys often ignore what they want and need, or don't truly know how to ask for it in an effort to make sure they're giving their woman everything she needs. This often can make nice guys appear passive instead of respectful and caring like they intended to portray themselves. 

Some women like a more thug guy because he displays the potential for two things: protection and providing.  Many thugs have this hustler mentality.  Meaning that if he needs it, wants it, doesn't have it, he's going to go get it.  And there's not a whole lot that can be done to stop him from getting it.  While it may be in a non-legal, messed up sort of way, what a woman is attracted to is that 'go-get it' spirit.  In other words, drive.  

Many of you nice guys have that drive, but because of what I mentioned before, that apparent lack of backbone or passiveness, you don't really show it.  You don't want to appear boastful, or conceded.  Many of you, because you are successful or are on your way to being successful, can come off as a bit complacent.  Too calm, too patient, too wait and see. Mostly because you're secure in your skills and talent and truly know, not believe, you'll get there. But women don't only want to hear how you're trying to move up, or how you plan to be a provider, they also want to be able to see your progress.  Because of this you are going to have to find ways to prove to her that you can be that provider and that you do have that go-get it mentality.  How you do that is up to you.  But you can't just be all talk.  

The thug also comes off as a guy who will not take any mess.  He will not be disrespected and will not let anyone that runs with him be disrespected either.  That often can make a woman feel like she will be protected.  Women need to know that if things get rough, stuff pops off, you as the man will be there to protect her from harm.  And because many of you nice guys don't often come off that way (because of that whole initial issue - see how it all circles back to that) you get left behind.  

Now I'm not saying that you jump up to every man that starts something or go looking for fights.  Protection isn't always that.  Sometimes it can be as simple as fixing something that she needs fixed yourself.  Moving her to the inside of the sidewalk and you walk by the street.  Letting her precede you as you walk up the stairs with your hand lightly on the small of her back, showing her that you'll be there to catch her if she wobbles or falls. Holding her hand as you guide her through a crowd. Not letting your friends get too disrespectful or rowdy around her if you see she's uncomfortable.  Taking her side in a debate, supporting her point (if you agree with it), in a group discussion. There are small gestures and ways you can show her that you've got her back.  

As a nice guy you have to find a way to show her that you are respectful, considerate, and concerned about her needs while remembering to still showcase all of the qualities that make you a MAN. Once you're able to really walk that balance, then the nice guy will no longer finish last.