PSA: At least try to be a little nice when someone isn't doing so swell.
EDIT: This post got removed since I accidentally put in miscellaneous, whoopsy daisy. EDIT 2: Holy shit Im retarded and did it again im so sorry.
So I just came from a game where my Tristana was constantly berating me all game, and while I admit that I wasn't playing well, I had not given her any reason to just jump to immediate flaming other than me taking ignite instead of exhaust (I play so extremely aggressive that it's not even funny). So after one failed engage the first thing she says is: "Never play Shen support again, you suck at it". I proceeded to walk up, flash my Mastery 7, which had all of the mastery 6/7 tokens earned from playing Shen support, and said "Don't jump to the conclusion that i'm bad at something just because im having one bad game." That shut her up real quick (/rant over)
Now the point of saying all that is, instead of assuming that someone sucks dick at doing something, maybe think that today isn't their day, or maybe they are simply being outplayed. Don't instantly jump to the conclusion that your laner/jungler sucks dick simply do to one bad game.