Cesar Ruiz was pretty terrible for a couple of years. Not everyone "gets it" in their first year. But that doesn't mean they won't become good players over the course of their career. If Penning ends up starting for the next 10 years, nobody is going to care. There are certainly some things he doesn't do well. But there's enough to suggest that he can be pretty good, and you don't get there by sitting on the bench. You take your lumps on someone you think can become a good player, or you spend a lot of money of a FA that may or may not ever be available.