Mariah Carey and Nicki Minaj
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When Mariah Carey became a judge on “American Idol,” the reality series earned some serious credibility. But then they invited Nicki Minaj to join the show as a judge, too. Supposedly, Carey never wanted Minaj on the show because she was afraid that she would steal her thunder. But the studio executives overruled her. This led to a season full of drama, feuding, and snarky remarks between the two talented musical divas.