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.
Beating Dark Souls 2 without dying or using a bonfire rewards you with a ring that makes your right hand weapon completely invisible.
It isn’t worth it at fucking all, since there is a spell that does the same thing and is way easier to obtain (even in 2025 despite being a multiplayer rank reward). The spell and ring also have ZERO effect on PvE and it rarely matters in PvP when the animations of your body instantly reflect the size of your weapon to a good enough player. Like, I don’t need to see your Ultragreatsword to know that’s what you are swinging when your arm starts hefting the weight.