You've been invited for rage quitting/griefing.

If you were invited to this group, it's because you either rage quit from a game, griefed in an attempt to try to piss off a winning team, or were just generally being a douchebag (I.E. "OMG ♥♥♥♥♥♥ hacker!") Take this invite as a reminder that quitting doesn't make you better, nor does it make the bad men go away. Stop being a raging ♥♥♥♥♥ and maybe you won't suck so bad at this game.

Oh, and don't give me this "I play games for fun, not for serious" ♥♥♥♥♥♥♥♥. It isn't fun getting your ass raped, and that's why you quit the game instead of getting better at it.

Picture related, it's what leaving something unfinished looks like.