That's true too. You can pick up on it and know when they are getting all "horned up". I dated this Vietnamese girl many years ago that was very shy about sex, but for 3-4 days a month she got so horny it was ridiculous. I'd come home from work and she would be dressed in fishnets laying on the bed playing with herself. It was pretty awesome, she'd be so wet there would be puddles of juice everywhere.
I think what Van B says is pretty accurate, i don't think most women need an orgasm or have their butthole gapped, but they need the attention and to know someone wants them, it's more emotional for them. A lot of sluts i've met over the years just wanted to be loved, it's not like they were searching for endless orgasms, they wanted the attention due to most likely childhood issues. Just meet some strippers and spend time with them, it's pretty obvious it's not about sex, it's about money and getting attention.
Once you can figure out what turns them on, it's so easy to smash just about whenever you want. It's all a game.