personally, I think he's a massive twat.
he has a really punchable face. he sometimes makes it look like that he hit someone, even though the BB is very clearly going towards the next county over. and like everybody has mentioned, unnecessary headshots. yes, this is a sport where you shoot people, but hitting someone in the head on purpose is just being another level of bellend (I usually apologised for headshots, accident or on purpose), but then complaining about it when it happens to him is the one thing that gets to me.
my last reason, when he doesn't shoot women. they paid to get shot at, and you have a clear shot, and yet you don't shoot them because they're a girl. sure, its "polite", but again, they paid to get shot at, and it doesn't get you any closer to getting a touch from them.
i also find the "tactical voice" he does REALLY annoying. that voice that he does when he explains a mission/objective. just talk with your slightly less annoying, normal voice.
this is why he will never feel a touch of a women...