Making a wrong a right

[youngump]

Originally Posted by bainsey

Whereas this could be a protestable error (incorrect application of a rule), why wouldn't it be wise to simply fix it upon discovery?

The argument against changing it is that in general you can't go back and fix anything. If for example, the umpire judged that the appeal occurred before the runner got home, the run certainly wouldn't count and no one would say that the umpire can go back and change his mind.
The argument in favor is that no ruling is actually made here and it's simply a scorekeeping error.
I don't know that the book says anything about this, but I'm not sure how you can take the latter position without saying that it can be fixed the next day, or the next year, or forever.