Is perfection valuable?

Aim at perfection in everything, though in most things it is unattainable. However, they who aim at it, and persevere, will come much nearer to it than those whose laziness and despondency make them give it up as unattainable.

 - Lord Chesterfield

No good work whatever can be perfect, and the demand for perfection is always a sign of a misunderstanding of the ends of art. 

 - John Ruskin

I really like the second one. That's quite important, because a lot of artists, as they learn their craft, get hung up on Perfection, and it's a very sticky trap.