I hunt down achievements when I enjoy the game and the achievements sound fun and not busywork. If it's interesting side quests, minigames, or fun challenges, I almost always do them. I also like playing at max difficulty when it's fair.

If it's about going through a checklist to collect 100 feathers or spending 50 hours learning the entire game by heart to complete some hardcore challenge, I'd rather do something else with my time.