As a Lamb I have to say that some of the vocals on Mariah's recent songs have been an absolute mess. They mess around with her vocals by speeding them up to make it seem like she can do really good melisma but she ends up sounding like a chipmunk that can hit 100 notes in 1 second which is obviously impossible.
The vocals on Heavenly (No Ways Tired / Can't Give Up Now)
Britney's vocals on S&M are always dragged because it sounds like she has a blocked nose and the bit where she sings "make my body say ah ah ah" is so cringe because she tries to sound sexy but sounds like a robot having an orgasm.
Kelly R's simply deep had some songs that clearly had flat notes and offkey harmonies. The fact that they allowed that music to be put out is proof Michael was out to sabotage her.