Do You Believe In "Untouchable Classics?"

[Koh]

As the title plainly states.  What do I mean by this?  Well, this question has three embedded parts to it:

1.  Does there exist a piece of media that you believe could never be polished further?  And if so, why is this?
2.  Does there exist a piece of media that you believe could never be rivaled or surpassed in quality?  And if so, why is this?
3.  Does there exist a piece of media that you believe, if remade, could never capture the essence of the original?  And if so, why is this?