I don't do it bc I don't feel comfortable doing it with someone I just met and I don't know anything about them as a person or their std status. I've done casual sex when i was young and wild, it was fun at the time, but I'm over it and its no longer appealing to me.
However, I don't knock those who do (never understood women who r concerned so much about other women's vaginas) and none of my reasoning for not doing it has anything to do with what some guy thinks. I think thats where most women trip up. People have these 3 month, 6 month rules, etc...and then be mad when they STILL get dumped like yesterdays garbage once they give up the goods. Waiting is not a guarantee he's going to stick around, so if you do wait, do it for YOU.
And yes, I also know folks who have slept with guys on the first date and they had long lasting relationships. No its not the rule, but I think it happens more often than most like to think. I think it makes some women who are on their moral high horses feel better to think that it never ever happens that way.
Also...the guy who is scrunching up his nose and going "oh I don't respect her...she's a HO bc she gave it up to me on the first night"...I wouldn't want him anyway bc obviously he is extremely hypocritical which is a huge turn off...being that HE also participated in sex with a stranger.