"How is finding good UDFA's indicative of poor drafting? "
It's in an indication that you have roster spots to fill. You're assuming because they made our roster they are good. That's not always or even often accurate. We have suffered from a lack of quality depth for a few years now. I believe that is in part due to poor draft results.
Every year we drool over the UDFA of camp and rarely do they turn out to be more than a warm body. The Tramon Williams and Sam Shields of the NFL are rare and we haven't had one in a while.