Players aren't really intended to grind out full sets of crafted purple gear during the leveling process, it's a waste of time. In the time it takes you to do all that you could level to the point of wearing greens that are more effective. Now, when you're level 50, yeah, spending time on that will be worthwhile, or when lots of people have level 50s and want to twink out their new alts in purple gear, it'll be worth the trouble. But while leveling? Getting the occasional purple item while leveling is just a cool bonus and should be seen as such.