He Was A Great Face Of The WWE
The Miz did a lot of work as WWE Champion in the run up to Wrestlemania 27. He appeared on various talk shows as well as all sorts of functions for both the WWE as well as their associates. The thing is, unlike many heel champions, the Miz was clever enough to use this in a way that didn't make him seem genuine. While he was obviously really on the talk shows to promote WWE, the writers and the Miz himself on Raw made it perfectly clear that the Miz was promoting himself- the WWE just happened to be along for the ride. This allowed an interesting angle to be opened up for the WWE, with Miz being the corporate shallow champion with no respect for the business against a challenger in John Cena who actually did respect the business and its heritage. It also helped feed into his inferiority complex as the WWE played off the idea that he was a 'soft' champion, who won the title by fluke and couldn't keep it cleanly. So with all this going for him, why wasn't the Miz's reign as good as it could've been?