I doubt forms can be perfected, in which case failure would always be a component of art. I'd also be curious who determines perfection. But supposing forms can be perfected, why shouldn't art be a process of discovering new forms--in which case, experimentalism and imperfection are a constitutive part of the aesthetic process? Perfection is rather boring, after all. This assumes a set of normative values that art should preach. Order and harmony aren't transparent and apolitical concepts; they can be appropriated for political ends. The problem with art in service to normative values is that it never challenges us to think otherwise. This all sounds a bit Platonic and utopian, which is unusual for you (although the ideas about art are vaguely familiar).