I used to think you could draw conclusions from all this, but I have since changed my mind. I've had sechs with girls within hours of meeting them on a first date. The longest I went was 5 dates(had her top off on date 4). Sechs typically happens on the 3rd date for me.
-The girl that took 5dates before sechs happened had high interest, emotionally mature, rational, told me she loved me at month 3. Then told me we weren't right for each other at month 4.
-My 5yr ltr that was emotional, insecure put out on date 2. She complained about giving it up that early as well. But that girl loved me lots and still thinks of me.
-Last summer I had a girl that put out on the first date. She was very rational, no mental issues. She was super horny and hadn't been laid in several months. Dated her for a couple months with no issues.
It all depends on how horny they are, interest level, how much time you spent talking to them before hand, what they are looking for etc.