Among the personalities comprising the judges panel on American Idol, Mariah Carey is without equal. That is true for now as well for any other combination of judges who have been on the show. Simply put, Mariah Carey is the most qualified judge to be on the show. So why isn't she a better judge?
For someone who has carefully constructed an image as some super diva, Mariah has certainly seemed to be easily overwhelmed by the moment and the attention foisted onto her as a judge. What's more, she's swallowed her tongue on more than several occasions when even the most casual viewer knew what kind of critique needed to be dispensed.
TV Guide comments about how Mariah's judging method isn't really helping anyone at this point.
"What's going to benefit a contestant more at this point: telling them how great it is that they've made it this far in the competition, or nitpicking a little bit and giving them the pointers they need to go even further? When Randy Jackson is offering more thoughtful commentary from the judges' panel than you are, there's a problem."
Just as Keith Urban has proved, you can be critical but charming. And over time, the audience, as well as the contestants, will start to ignore a judge who never offers anything in the way of compelling advice.
Besides, aren't most of the viewers so preoccupied by hating Nicki Minaj that a little criticism from Mariah would be largely dismissed as just 'helpful mentoring'?
Source: TV Guide