Just sharing my thoughts :

1) The guy who plays anivia just to wall you in the enemy team
2) The one absolutely sure that you can play AP pantheon jungle
3) The guy who wants all your team to take smite so you can do dragon quickly
4) The guy who picks urgot when everyone in your team is a tank, so you end up doing 0 damage and losing a game that last 30 hours because they can't kill you but you can't kill them either.
5) The guy who smites a minion, so you don't have it for baron and the enemy steals it from you
6) The guy who wants to do baron at 15 minutes, baron just got a pentakill
7) The guy who starts a game 1 minute before he needs to go somewhere
8) The guy who always walks away with 1 HP whatever you do
9) The AP MF (yeah we all know this one don't we ?
10) The guy who takes smite too so he can steal your blue buff when you play jungle (oh this guys picked garen by the way)
11) The spear from Nidalee that ALWAYS end up in your face even if 4 champions and 150 minions are in front of you
12) The guy who instalock, doesn't say a word, mess up the game, but end up carrying like a boss
13) When you recall next to baron, that guy who comes and just throw a spell at it so baron attacks you and you die.
14) That blue buff that reset 4456232 times

Add yours too

15) Those guys that just join games just to facilitate you getting repeatedly facepalmed by the enemy, who are probably all on skype together s****ering at your frequent demise... Pinging for you to initiate with 1/3 health and then after u initiate they swoop in to take what little remaining health the enemy might have left.

i hate the guy that always shows up after a 4v5 is about over...cleans up the mess...then wants to teach you how to play cause their k/d ratio is better than yours.
i also hate that guy that waits in bush for like 5 minutes jsut to ambush and kill you, even though they lost more in cs from the lost time than they got from killing you, then talk trash about it

I hate the guy that comes into the match, manages to gather enough cs to buy a beginning item and then never comes back from the store whether it is because he is afk or is just so enthralled by the plethora of items that he could potentially purchase that he decides to go through every page to see every possible item and build, then when he is finally done standing at the summoner's platform; He comes back just long enough to feed the enemies, call his team mates Noobs, and then disconnects. Oh and just for a lovely top to the perverbial **** cake, guess who pops up in your next queue?

The guy who is never at fault for a loss. The one who can't stop harrassing whoever gave first blood (and if it's him, it's the the fault of jungler/support not backing him properly (when he's the idiot who overextended with no wards in place).

The AD carry that claims he won the game by himself and that is support didnt help.

I hate the support that doesn't ward, then rushes the enemy bot duo and gets killed while I'm all the way behind my minion wave, and then proceeds to blame me for being 'a terribad adc, etc.'

I hate the players who expect a blitzcrank player to land every pull, and to somehow pull champs from behind their minion waves.

That guy who sneezes on your Bob Ross painting.

The solo tops who cant solo top.. never ward lane, always push, always die, and all they do is blame their jungler for no ganks to a pushed lane.