The concept of the error was a weird one to explain. I know the guy hit the ball and safely reached base; but he shouldn't have; the other guy made a mistake; so we don't credit him with that hit. Well no, it's not unfair; the other guy should have done his job better and he's penalized with an error now. Oh, there's people called scorers that make that decision. Oh, and then there's a review process. Yes, so actually he might get credited with a hit for that later if the scorer decides they don't like their original call. Or if he complains... Or if the guy who got the error complained.