I think it is a mess because ADELE is still fairly new, her success was so sudden.
We never know what will happen to her next year, if anything she could end up like Leona Lewis #noshade
Also I feel this list misses Britney Spears, though Femme Fatale's numbers are a little underwhelming, the singles and stability have been rather consistent.
Gaga & Adele are good on the list but Bey hell no, Shes flopping. And Britney fans I don't see whats the big deal are Queens in the legend trinity, she doesn't have to prove ****.