A good achievement/trophy system is supposed to make you aware of just how much more there is to see.
Achievements are literal dangling carrots in front of each and every gamer who has ever grabbed a video game on Steam, PlayStation or Xbox. The reasoning behind them is to keep the player engaged with any video game for just a while longer. “I’ve killed 37 bad guys with headshots, maybe if I force myself to play against my usual style and force this unnatural gameplay style for just a little while longer, I will pop the trophy, even though I have already beaten the campaign mode”, might think the gamer who cares about them. Others might find them condescending – and they might have a point, but to each their own.
I have a confession to make – throughout my years of gaming in the past two generations, I’ve unlocked over 150 platinum trophies, the one that pops up once you’ve unlocked every other trophy in the game, across PS3, PS4 and PS Vita. And as much as this might seem like a waste of time, there is a good argument to be made as to why they matter without making the achievement seeker seem like either a bumbling moron or someone obsessed over leaderboards or rankings.
The purpose of the trophy system is to lengthen the time someone spends on a title before moving on, and neither trophy hunters nor people who don’t care about them would bother arguing this point. In contrast, way back when we just played the game, beat it, and enjoyed it for what it was. The thing is, though, some titles might have had a built-in system tracking your progress, and telling you how much of the game you have seen – for example, who could forget Symphony of the Night’s legendary 200.6% map completion? Or, is it possible that there are more whistles in Super Mario Bros 3? Can Cloud possibly revive Aerith? Completionists have always had ways to keep a game from giving them things to do. The point is, lengthening a title´s duration by itself is not necessarily a bad thing, at least not if there is content someone might miss if they just stick to the main campaign.
Not every game “ends” when the credits roll – think about Nier: Automata’s many routes and endings, or how some titles (The Witcher 3, Fallout, Grand Theft Auto) allow free-roam after someone has beaten the big baddie. Some games even encourage you to replay them and make different decisions, side with different factions and try different approaches, because, are you really gonna settle for Crono being dead after fighting Lavos? Is that Silent Hill 2 ending the answer you were looking for? This phenomena is the most prominent in RPGs but also seen in all kinds of titles. A good achievement/trophy system is supposed to make you aware of just how much more there is to see – about how there is no reason to say goodbye just yet. For all you know, the adventure might just be starting, or things could turn out differently.
Competitive gamers who see trophies or achievements as literally something ‘to achieve’ might enjoy more milestones such as “kill X amount of enemies a certain way” or “win X amount of matches”. I won’t judge anyone’s tastes, but those seem arbitrary and the least interesting type of objective. A good mix between the two kinds could be something like “explore 100% of the map”, or “retrieve X amount of collectibles”, which is both something commendable that could truly test a player’s mettle, and something that just keeps them seeing and noticing new things. Having optional superbosses, as well, and getting a trophy out of it is a compelling reason as any to both try to tackle them and brag to our friends once we succeed.
There is another compelling reason to unlock achievements, but this one pretty much only matters if the person playing is really young, or if they live somewhere where games are not really affordable. Gaming can be an expensive hobby, particularly outside of the so-called developed world, and many gamers might have to settle for playing one or two new titles a year. This type of gamer might be more inclined to get the most mileage out of every title. MMOs or sagas like Destiny or Battlefield shine for being basically endless by providing both a social environment with a gameplay loop, where even if someone has achieved max level, might be inclined to come back for more, even if just to see their friends. But for single player experiences, it is easier to just get something out of it by trying to go for the final trophies that you are missing.
All of these reasons intertwine to make milestones matter. Some of us just want to feel that we have left no stone unturned, and seen everything the game has to offer. Being a completionist and unlocking every last secret feels good because we feel like we were in the right when we made this purchase. The other side of the coin, though, is that trying to go for that rare item that requires a 0.001% drop to occur can ruin a game for anyone. The key to a good system is a perfect balance between skill, tickling player’s curiosity and providing a guideline for just how many more things there are to do that we might have missed – without ever becoming too much of a grind. The main reason why some gamers do not care for achievements is because very few ever achieve this sweet spot.