I only play single player games, but couldn't care less about achievements. It is all about exploration, story, game mechanics and modding for me.

People treat achievements as if they are a status symbol. I mean sure, if you don't know what else to do in a game, they can give you some goal, but IMO the game itself should encourage you to reach the goal, not some external badge. The experience doing the task should be the reward in of itself.