There are exactly 5 (+1) things that make an achievement a bad achievement. Straight to it:
Make the player buy a DLC
Do you have achievements in your game? Great. Have you released a DLC? Good! Now you can release a new achievement dependent on the DLC and put it into the base game. Example of this achievement:
Xotic‘s ‘Even More Perfect’:
Perform a perfect chain with a point multiplier powerup active (requires Pipe Works DLC)
Make the player destroy our planet by producing even more CO2
Do you want to make players play your game for an extended ammount of time? That’s obvious. Please, release an update, add more challenges, whatever. Just don’t reward us with an achievement for a *really* extended playtime. Example:
Garry’s Mod‘s ‘Addict’
You have wasted a year of your life playing GMod!
Make the player play with you
It is a bad idea to put in an achievement requiring players to play with you, a developer. Especially, if you rarely play your own game. Practically not achievable. Example: Garry’s Mod again (WTF is wrong with you, Garry?):
Garry’s Mod‘s ‘Yes, I am the real garry!’
Play on the same server as garry
Make the player play on a specific (non-repeating) occasion
It’s perfectly fine to have an achievement like “Play on April Fools day.” It happens and will happen every year, so it is unlockable for everyone. What the flock has lead some developers into thinking that having an achievement connected to a thing like “You have played the beta” would be a good idea? How are we supposed to unlock it now? Example:
PC Gamer‘s ‘Beta 1 Tester’
This achievement is awarded to the helpful testers of the first Beta
Make an achievement practically unobtainable (not technically) after some time
Ok, let’s assume you have an online scoreboard in your game. It is fine to award players for eg. having finished a race under par time. But seriously, who could have thought of having an achievement like “Get into Top 10?” What is wrong with that, you ask? Nothing, for the first few days. But after a few months the probability of getting into the Top 10 quickly approaches 0. Look at Trials 2, for example. After being released 4 years ago, these are the points of the Top 5 players: 6199.97, 6199.56, 6199.01, 6198.80, 6198.31. You get the idea? Now, you may ask what kind of sick game could have an achievement like that? Ohoh, we don’t have to go far, my friends, it’s Trials 2, and it went even further. Not Top 10, not even Top 5, you have to be the one!
Trials 2‘s ‘Top Dog!’
Reached number one position on a track’s leaderboard. Now let’s see you STAY there..
Sadistic bonus: Make the achievement not achievable in the game itself
Yes, there is an achievement like that. Make a nice poster, make a movie about the game, write a nice review… Y’know how it goes.
Trials 2‘s ‘True Fan’
Awarded for being downright awesome. It’s not about performance on the bike, it’s about being seriously cool.
To sum it up, my special eff you goes to every developer who thinks including an achievement inspired by this list would makes their players cry out of joy. It makes us cry. Just not out of joy.