When I'm moving to help gank a lane, say so in chat, and have the person/people in the lane get aggressive before I'm even close and scare the target away... usually to then yell at me for "OMFG, you let him get away, N00B!"
When I'm playing Bot, have my lane mate AFK, get the enemy Jungler help with ganks and then have the team yell when I lose the tower. "holy crap, i hate playing with idiots!" Well, sorry MrPro for not being able to 1v3 early game when I haven't been fed...
People that complain about super obvious mechanics. Randumb: "OMG, I absolutely HATE Teemo's Shrooms!! SO annoying that they stealth!!" Me: "buy Oracle's Elixir." Randumb: "Why the **** would I buy that?" *proceeds to feed Teemo kills by blindly run into Shrooms*... Me: >_<
That, or seeing an enemy Blitz or Amumu start running for us with their team in tow, and the weakest person runs forward yelling "ME, PCIK ME TO GARB/PLUL!!1! :D"
People that ignore AoE. Anivia drops an AoE on the ground, team mates don't move (I'm running out). Pantheon's marker for his Ult appears on the ground while his team is getting closer, no one moves (I Flash out).
People that assume that a single death is the equivalent of giving everyone on the other team Baron and a free 5k gold. A Tank and I (full health Draaaaaaaaven) run into a group, we kill 4 of them, I die and the Tank backs off to heal. "OMG Draven, stop feeding!!" or "Why did you engage if you just died?!?" This is especially annoying when I'm going positive and aren't close to having the most deaths.
.: PSN: Tamoketh :: DRM is the fix no one wants, for a problem you can't avoid :. .: You gotta be can we do you think if we can make a should just be alone? :.
The whole "I called mid/jungle/adc/etc" first thing. What are we? Children? Sure we can respect who wants what, but just because you called it first mean that if you don't get it you have to rage and sit at the base. -.-
The most annoying people are the ones who when in the champion select, select a troll champion pick and summoner spells to try and bait someone else on the team into dodging the game so they don't have to.
It's even worse when if you call their bluff they decide to go all the way if their troll picks and actually let the game start thus screwing your team over
If you are Amish and are 100% proud of it, put this in your signature.