Not quite an accurate quote/translation, and unattributed to boot.
Antoine de Saint Exupéry: "It seems that perfection is attained not when there is nothing more to add, but when there is nothing more to remove."
Or in the original French: "Il semble que la perfection soit atteinte non quand il n'y a plus rien à ajouter, mais quand il n'y a plus rien à retrancher."