When you die, you don’t know you’re dead, and only those around you are affected. Because . . . you’re dead, and there is nothing you can do about anything at this point.
It’s a similar situation when you’re genuinely ignorant. You don’t know just how ignorant you and your actions are, and those around you can be affected in ways you may never understand. You have some power to influence and maybe fix the damage you may have caused, but that requires you to realize your ignorance.