What lures you in to approach/dance with a girl at a club?

personally I believe its the body language, and if she has that certain confidence level about herself while she's out there dancing. eye contact with the guys looking at her makes her seem a lot more approachable for a dance.

I used to go clubbing 3 times a week and approached tons of women so this is what went thru my mind as I picked a victim :p
There is are lot of things that go thru when selecting a girl and the first one is, scanning the dance floor, and making eye contact. So if I walk to a dance floor,and suddenly I see a girl looking at me, then I make eye contact and I gravitate to that girl; of course, by the time I decided if to gravitate or not, I already determined if this girl is cute enough to dance with, cause yea, lots of fat girls on teh floor, so not gonna go to those.
If there is not a girl that made eye contact, then I scan the floor to see what girls are on their own; many times, there is a group of girls and all the girls in the group are dancing with a guy, and one girl is by herself. Again, if the girl is cute, I go to that one.
Now, if all the girls are on their own, then I also scan to see what girl is dancing with sensuous movements. Once I spot a girl that looks ready to get down, I go to that one.
Now, lets say there are two girls that are moving the same way, then I will go to the one that is dressed sluttier; for example, many times I see girls wearing blue jeans and like a sweater type of shirt. Of course, that's the girl to be avoided because she is dressed too boring or conservatively to be any fun; the girls that got all the make up, or got tthose tight black pants with tank tops, those were the first ones on my list. Also, many times I saw girls that were dancing very clumsily, so those were easy targets cause my line to them was, 'wanna learn how to dance?' And it only took a couple of hip movements to show them how to 'get down.'
What you have to keep in mind is that if you're dancing with a bunch of girls, many times guys won't approach cause the female friends act as scarecrows; in other words, lets say that you do want to dance with a guy, the guy comes to you, and then one of your friends tells you he is not cute enough, and he separates you from the guy. So I have had friends that don't bother to approach girls dancing in a group. As for myself, I never cared; anybody was fair game. :D