Several things:
(1) "I have X problem with my body. I want to ask LPSG for advice instead of going to a doctor."
(2) "My life is shit except for LPSG. I'll post here every 5 seconds until my life gets better."
(3) "I'm kinky as hell and didn't read the TOS. I want to post everything I can that violates the TOS so I can attempt to return with a different screen name and complain about the moderators."
(4) "I want to beat a dead (political, cultural, asinine, take your pick) horse. I'll demonstrate how obnoxious I can be until I'm banned."
(5) "I'm on a big dick site but can't stand fags. So I'll post my big dick and then get upset because all the fags compliment me on its size."
(6) "I have no idea how to be a human being, but I know my dick is hard and I know it gets hard over female tits and ass, so I'll go over to the Women's Issues section and see if I can get some attention. Over there, I'm sure women are just waiting for me to come on to them."
(7) "I'm not proud of my own body, so I'll borrow several other people's pictures and pass them off as my own. Even though each is a picture of a different person. I'm confident that I'll be successful at fooling everyone."
(8) "I'm new here, so I'll jump in with both feet and make a big splash without listening to see what the conversation's about. I'm sure I don't need to assess the context before I insert my $0.02, because I'm confident that anything I say will be important enough to share."
(9) "I'm (in/circumcised, nudist/not, straight/gay/bi, natural, shaved, pierced, a modest person, a private person, etc.) and think everyone should feel exactly like me, because I represent the entire human race. So I'll spend my time at LPSG evangelizing to those who disagree with me--particularly those who disagree the strongest. I'm sure I'll be successful."
(10) "I'm larger than you, and you, and you, and even you. I'll spend my time here at LPSG making sure that I share my enormous size, because as everyone knows I ordered my genetics from a catalog--it wasn't just chance."
(11) "Even though that friendly person says his or her sexual orientation is X, I'm sure it's Y, because why else would that person be friendly? And besides, his or her body is so attractive that I can't stop myself."
(12) "Why actually have face-to-face conversations with other people? I'm sure Skype, kik, and other modes of communication are sufficient. After all, I'm just here looking for sex."
NCbear (who's feeling somewhat snarky at the moment, in case you hadn't noticed--and who's sure he can think of more, if he had another half a second to cogitate)