Why do two wrongs make a right? Learn from your mistakes?

People say that two wrongs don't make a right. That could mean one of two things. I understand that it's supposed to mean that if someone does something wrong like spit on someone's shirt, and another person, I don't know, spits on their shoe, that doesn't make it right. But what if you did something wrong, and then you did it wrong again, and then you learned from your mistake and did it correctly the third time? (THIRD TIME'S A CHARM!!) I would say that those two wrongs made a right.