23 virgin here
It takes an incredible amount of effort to get sex. Even if you are an incredibly confident, good looking guy, it takes a great deal of time and effort. First off, you need your own place. With the large number of young adults who are living with their parents until they finish college or are able to find employment following college(which can take a long time), this is an immediate roadblock to sexual activity. One night stands or short lived flings are almost impossible. You can't invite yourself over to her place, and most girls won't be the ones to push for sex, they want guys to do the pursuing, so she likely won't invite you over either.
The other alternative of course is an actual, legitimate relationship. But this is incredibly difficult too, as it takes an immense amount of time, money, and effort to keep a relationship healthy and a girl happy.
A combo of the above is the main reason why I haven't screwed yet. It's just too damn hard. My life is stressful enough without dealing with the mindblowing pain in the ass that is a relationship. And due to my housing situation and aversion to clubs/bars(bad loud music, douchebags, and low quality skanks? no thanks), one night stands or short lived flings are out of the question.
Not to mention, I do have some self confidence issues and I'm very pisspoor at talking to people in general. Plus, my sense of humor is the type where I'm a laugh riot among my friends, but around girls I'm a pariah. So even if I had the desire to put up with the massive amount of soul crushing stress that comes with dating, there is a great deal of doubt as to how successful any attempts at it would be.
Anybody know what the statistics are on virgins under a certain age? Like how many guys below 30 or 25 are virgins? I think it should be a pretty high number. If it's not, good chance guys are lying due to the stigma society places on virginity.