- "It is a fact of life that women know within seconds of meeting a man whether or not they would have sex with them.... The first time we hung out we had sex."
Conclusion: as soon as you even suspect that a woman may have disqualified you, NEXT her and move on to the next one. When in doubt, NEXT. If you're not sure, NEXT. If it's a little confusing, NEXT. If she's sending mixed signals, NEXT. If you are getting anything but genuine enthusiasm to see you, unnecessary touching, and enthusiastic physical contact, NEXT. Do not hesitate, ever. No more than two dates should ever be necessary to make this determination from the male perspective.
Here is why this philosophy works even if you were being overly harsh and she didn't actually disqualify you. By rejecting her and moving on, her perception is that you disqualified her, thereby raising your status vis-a-vis her own. Furthermore, by rejecting her, you've burned a place for yourself in her brain ; women remember men who reject them far more vividly than the other way around, because it doesn't happen anywhere nearly as often to them.
So, ironically, if a woman is not definitely and immediately interested in you, and clearly signaling that interest, your best move is to NEXT her. Your worst move is to try to qualify yourself to her; the harder you try, the less progress you are going to make. Instead, cut contact and move on to the next possibility. If you run into her later, or if she pursues contact with you and demands to know why you didn't keep pursuing her, just tell her, quite honestly, that she didn't seem particularly interested in you. Naturally, you didn't see any point in spending time with someone who wasn't interested when you could be spending it with women who actually are interested.
You may be surprised at how much more interested she will be the second time around, so long as you maintain your frame. And if she still isn't indicating any renewed interest, then congratulate yourself for saving time, money, and opportunity cost.