We all go into autopilot sometimes. So, you know, we're on a marathon session to level up, and we're mostly just sort of clicking by instinct. You belatedly realize, however, that you were in the middle of a quest chain. The reason you realize this, sadly, is because you're at the penultimate stage of said quest chain, and the questgiver is making references to all the work that you've been doing to reach this point... when you don't really remember most of what you've been doing up until now. There might have been something with fish men? Or the other fish men. It's all kind of a blur, really.
Lore is important, and few people would argue that, but when have you managed to completely miss every bit of what's supposed to be going on? Did you not read up the backstory in the manual and therefore not know that the person you're fighting unleashed horrors on his own people? Did you forget about an NPC that is actually kind of important in retrospect? Or did you just steamroll through things and only find out later that there was an overarching reason for all of this?