Lady Gaga's entire career has been an A/B test. She started out as a singer and songwriter who actually poured some meaning into her music, and had no success. Then she seized the common pop chords, added a heavy back beat, stripped her songs of any meaning, and started wearing meat dresses. I'd say that B worked for her.
In addition, she's part of a larger A/B test being run by the industry. Music producers have a nearly unlimited supply of cookie-cutter musicians who they can produce in different ways to see what works. They're expendable, so when they fail the producers can move on and the musicians can go back to playing local clubs or whatever they did to get the producers' attention in the first place. I've known several musicians who got popular in a local scene, got a "big break" and released one heavily-produced album that sounded nothing like their previous work, and then faded back into obscurity. Every now and then one of them breaks big and the producers can cash in for a few albums.
