Something that's always puzzled me is what the game means when it says "Safe to log out". Like if I'm in Mournhold and I hit Log Out or Quit it just goes right off, but if I'm in the open world or some of the other cities/towns it does that countdown when you log off and if you hit quit it "warns" you about not having a safe log out.
So what exactly does it mean? Safe from NPC's? Safe from data corruption?