naw, i think a lot of times it's like the thread started said.Well, if the guy is actually looking for a relationship and the woman is well, holding out on the puss doesn't work against the purpose she has. I doubt not having sex will stop you from considering someone who still exhibits the qualities you look for.
even if at first you were looking for a relationship, if you feel like the girl is trying to use the puss for emotional blackmail (to get a relationship) or you feel like she's not the type of girl who usually makes people wait but for some reason she's making you wait, just the fact that you're thinking that (right or wrong) now you feel like she's playing you for a sucker. and since you feel like she's playing you, you're gonna want to win the game. and to win the game, now it becomes about sex. eventhough that wasn't your original intention. both genders need to just learn to keep it real. (this will never happen)