Perfection is not the heaven we seek but the Purgatory that we secretly dread, knowing full well that once everything is truly perfect, there is nothing else to strive for.
Life is imperfect, and it is the imperfections that make it worth going through. While there is never anything wrong to aim for perfection in one's craft, what do we do after achieving ne plus ultra? Profit perhaps? Or maybe a sense of accomplishment? In the end, however, we all get a backlash of longing or the need to improve upon things further, be it the same piece or in other avenues.
Perfection is also relative, if not a myth, applicable only depending on who you ask. I daresay that the most perfect of lives are those that are imperfect. As any story goes, it would be pointless to have a protagonist go through chapters without struggle or not have at least one flaw. We've heard all the cliches from various chick flicks, "she had the perfect live etc.," but the common denominator always seems to be the longing for something more, beyond the this fabricated notion of a "perfect life".
Practice makes perfect, but the true worth and value of anything and everything isn't its perfection, but the practice that leads us to the point closest to perfection.
"To stand still on the summit of perfection is difficult, and in the natural course of things, what cannot go forward - slips back."