‘Perfectionist is the term you are reminded when you think of Amir…. But in most of his interviews you may also get a feeling that he is child like innocent.
But this child quality may be something that makes him a perfectionist, because he will not give up, unless he is satisfied. This may be because he does not pay attention to people around him who may be irritated or frustrated and also the fact that others may not think that the point he is making is not very important or it is way too important meddle with.
He has a dialougue in tare zameen par where he says most scientists were considered fools before they were recognized as genius because they were different and this uniqueness makes them think differently. Exactly like him where his innocence lets him be the perfectionist he is.
And we also see a characteristic of him, he is ready to take suggestion from any one, if it is good enough and he also says he can watch a movie just like an audience being completely engrossed in it, he has the ability to detach him self.