Either one or both works.
Mine is completing the Pokedex in the original Pokemon games. All you get is just Professor Oak giving you a wink and a small few second cut scene. And a congratulations text. Imagine spending all of your time then, getting all 151 and even 252 pokemon just for that? Yeah no thanks, I never completed the pokedex.
Going the Joja-Route in Stardew Valley. I say this mainly because, it is what you make of it. You forfeit being able to complete the Community Center by earning things, when you sign your soul away to Joja. What I would’ve liked is seeing Pierre go out of business completely. I just think that would add a route of depth in the game where you have to make ends meet through Joja because Pierre is permanently closed.
But, that doesn’t happen, he’ll still be in business despite his depression about Joja running things. Kindof ruins the whole concept of doing it for the achievements even.
I’m also on the spectrum. Sometimes I think the spectrum is so wide as to be functionally useless for describing behavior. I feel like my comment maybe implied that I think less of people that feel compelled to 100% games, which is not the case. I just have different compulsions.
I’ve been gaming for over 30 years, and probably have thousands of games in my digital library. I don’t think I’ve gotten all of the achievements in any of them. I tend to predominantly play rpg’s, and other games with a strong narrative bent, and I try not to peek at the achievements, so as to avoid spoilers. I appreciate when the developers hide them, so it isn’t an issue.
I’ve seen many people argue that achievements have had a net negative effect on gaming, and I tend to agree, but I don’t really have strong feelings about it, since it typically doesn’t affect my experience very much.