What does achievements do for you?

Since MS brought in achievements, i personally have started playing games for longer, and also for pointless reasons. For example i have played a number of rounds on GeOW just to get 100 revives, where i have concentrated on picking people up rather than trying to kill others, just for 10gs. Stupid i know but i am a naturally competitive person.

This though brings up a certain problem. Achievements have started to change gameplay habbits. We all know the guy who just chainsaws or picks up the same weapon every round.

I would like to know whether achievements have increased the number of hours you play games, but also whether it has annoyed you. Any opinions are welcome (and other poll answers

They have ruined my life.

Funny you brought this up, I was just talking about this in another forum recently.  I started to get annoyed with acheivements when that Old Spice rewards thing came up.   I played a few games and got as many acheivements as I could.   I started doing tedious non-fun things to try and get more points to reach the goal like collecting those stupid coins in Lost Planet.  Then I actually contemplated renting bad games like King Kong and TMNT just so I could get the stupid points.   This is when I came to a realization that I was addicted.   I dont wanna waste my time playing crappy games just for points or some tiny reward.   So I cut myself off and went cold turkey.  I had a pile of PS2 games waiting from christmas to be played so I started playing those games for... gasp... the pure fun of it.   I've been clean and sober from acheivement points for a month and a half and haven't looked back. 

I sorta like the idea of getting things directly for acheivements in games.  Like in Gears of war you beat it on insane and unlock a special gamerpic.   I would much rather get themes, gamerpics, etc than points.  I used to love acheivement points now im not a fan.