Katy Perry has just completed a space mission which has me convinced that American Idol was right to replace her with Carrie Underwood.

A source shared how Katy Perry allegedly feels about returning to 'American Idol' -- and how she hasn't watched Carrie Underwood judge.

Although Carrie Underwood almost didn't compete on "American Idol," she ended up winning Season 4. But her skills on the stage aren't translating well into her role as judge. The "Before He Cheats" hitmaker replaced Katy Perry as a judge in the reality competition show's 23rd season,