Well this isn't always necessarily true... I was dating a girl off and on for about two months... I've only seen her three times, we never had sex... We came close on the first date...
I was interested in trying to get her in bed, but then I lost interest... I went ahead and had sex with two other girls... One that I've known for about a year and a half while I was dating my last gf (she was a waitress at a restaurant that we used to go to) and another girl I dated last year...
Super hot girl, great body and awesome in bed... We had a disagreement, I was going to go back with the girl I was seeing for two months but didn't have sex with... But then she did something that pissed me off... I was wrong for getting pissed, it was in her right to do it, I guess... She met another guy and kissed him, then spent the night with him... Supposedly they didn't have sex, but I never forgave her for that and stayed with the second girl, whom I'm currently seeing now...
Point is, that one of the only girls I've ever had sex with on the first date is my ex-wife and that lasted for 12 years and we had a great relationship and sex life... Interestingly enough, she had only been with two other men, her ex-husband of 14 years or so, two years dating before marriage and her first bf, who was killed when she was about 18... So she was single for about three years before we met, but didn't date anyone else, since she was working trying to support two kids...
I never judged her for going to bed with me on the first date (only a total dickhead would do something like that) I fell in love with her and still love her to this day for giving me a beautiful son... The sex with her was awesome! She did everything I wanted and I really loved her body... I guess we had a great connection... That's probably what it comes down to, not playing games or making someone wait, or the game some men play by trying to get the woman to make the first move, making her doubt her own attractiveness, or women making men wait... It's about a connection if it's really there it is, if it's not games just delay the inevitable...