Biggest Killjoys of gaming

In case if you don't know what a kill-joy is, it is something which ruins the fun of playing a game. So, what do you think is the biggest kill-joy of video gaming?
I have to give the award to the 'low-health beep' thing, which is used on most Zelda games/ Pokemon games/ and some more. I know that my characters are in danger, but do I seriously need to hear that stupid beep all the time?

So just an annoyance in games, I'd say when I'm playing a game that has ridiculously high encounter rates making it so you can't move ten steps without an encounter. Or when a game just throws out a ridiculously high difficulty spike out of nowhere.

When I'm on a streak of not dying and constantly moving through the game then GAME OVER.

Usually quit when it happens.

Also, sometimes when I play with others. Depends on how much my irritation level with them gets increased.

Hm...well honestly, everyone else has pointed out mh biggest annoyances, especially the Zelda beep. It's so annoying. More so in older games like A Link to the Past than in the more recent ones, but either way it's aggrivating.

Also, not sure this counts as it really isn't part of the game itself...but when you've played for a long time and the game just somehow resets itself. (like if a cartridge is accidentaly removed, or the power goes out)

Killjoys for me are the following: Annoying helper characters; such as Fi & Navi.. -_- Handheld games in which the game keeps telling me to 'take rests often'.. <.< Characters that are just clones of others I've played before.. (Final Fantasy XIII characters are all clones of past FF characters: ugh.) &: No plot interwoven into the game; just handed a pamphlet & told to read it. (No thanks I'd like my story interwoven into the gamplay thanks.)

Oh, there are loads of things that I don't like in my games. The one that causes me to ragequit the most is.....Luck-based events. If there are a lot of them, and the consequences of each individual event are small (as in Crusader Kings II, for example), then they can make the game more interesting - but if the outcome of a luck-based event makes the difference between winning and losing, that ruins it for me.

I agree with Queen: Annoying character whom are there to 'help' your characters whom are more annoying then helpful. <~< Shooters without proper strafing: don't even get me started on this.. >~> & A game with terrible controls. >~>