sometimes, the environment *does* cause you to leave like, but most of the times:

1. retards say "btm 1 moar, my fren wan join"/ "i wan up, my fren on top", then leaves after the game starts due to his fren is not playing/in different group
2. retards that think he's pro and others are scrubs, tells you, "u leavr la, u feed too much", when you are not the worst feeder
3. 11 year old kids that leaves the game during countdown
4. retards that cannot farm properly/bansai-charge enemy gank parties and blame other players for their incompetence

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recent scenario:

i got pwned twice in a row (so, i sux in this game) and a 'pro' requested me to leave without even checking the score sheet, where it clearly shown another player died 2 times more than me. I properly reasoned back and there are no words from him after that.

please inform people before leaving the game, you are playing with people thru internet and leaving without any notice (and self proclaimed 'pros' that harass people thru game chat) is rude .