An expert player is the nice guy who can be good at a game without being a jerk to others. A rookie is one who only thinks he's good at it and rubs it in.

If I'm gone then it's because of one of these reasons:
I'm playing something I can't pause.
Playing a game that cannot get on steam or cannot get the steam overlay
Very distracted
Did not notice and/or messege didn't pop up
most common: Actually AFK