When we learn the grammar of our language, the teacher does not stand in front of the class and proceed to say a large corpus of examples of ungrammatical sentences, only the correct ones are in the training set.

When we learn to drive, we do not need to crash our car a thousand times in a row before we start to get it.

When we play a new board game for the first time, we can do it fairly competently (though not as good as experienced players) just by reading and understanding the rules.