Games with achievements do better. I’ve lost my citation of the Microsoft data analysis that showed this, and it would be a stronger effect there because you have an overall score for total poundage of achievements there, but at least grant it for the sake of argument here because the point lies beyond this. Players are more likely to buy a game, play it more hours, and rate it more highly when it has achievements.
My question is how you set those up. Take two rather different MMOS: DC Universe Online and Yohoho! Puzzle Pirates. DCUO has hundreds of in-game “feats,” of which 23 are Steam achievements. Most of those are “beat the game as x” or items from the DLC. Puzzle Pirates has 220 Steam achievements, many of which are the ranks of the various mini-games. I haven’t played Puzzle Pirates in a long while, but I’m guessing it is not 9.6 times as much game as DCUO. DCUO gives you an in-game feat after any story arc or minor accomplishment, but outside the game you see one at the start and then come back for a few shinies when you beat the game. Puzzle Pirates thinks it better to give Steam achievements to you constantly.
I’m wondering to what extent these are business or game design decisions, or perhaps very little thought goes into them at most shops. Achievements seem used to note progress, to highlight nice touches, to reward people for doing difficult or poorly designed content, to incentivize perverse behavior in team games, or to reward very long term play of the “collect 1 billion x” sort. See Torchlight for examples of most, from “Find the entrance to the mine” through the course of the game, over the game’s various difficulties, and into long hauls (100 levels) and the WTF of “talk to the horse 100 times.” Alternately, see Grotesque Tactics with just 10 achievements, 4 of which you can/must complete in the tutorial, and I assume the game slows down that pace or else the whole thing must be about two hours. (I and many others must have picked this up in a sale pack, because 62% of owners never made it as far as the first fight.)
There must be some optimal system of achievements that serves as verbal praise to encourage and reward the player. (I’m also fond of games that give bonuses for them, like DCUO’s feats that grant skill points.) It’s strange how rarely achievements are treated as a serious development subject, since they affect how players play games and feel about them. Like drugs and other things that affect your meat brain, psychological tricks can still be quite effective even if you know they’re there.
If you don’t care about achievements, you don’t need to comment to tell us that again. Really.