Alicia Keys previously served as a coach on The Voice during Seasons 11, 12, and 14. During the competition, Keys shared expert critiques regarding the various contestants who tried their hand at the competition. But, during a round of "Spill Your Guts or Fill Your Guts" on The Late Late Show with James Corden, the "No One" singer gave her critiques for her fellow coaches who served alongside her — Gwen Stefani, Adam Levine, and Blake Shelton. She even ranked the famous singers from best to worst during the segment as she chose to answer one of James Corden's questions in place of consuming one of the gross concoctions that the show made.
While Keys was able to drink a spicy salmon smoothie instead of answering the question about her fellow co-coaches, she chose to rank the singers based on their vocal abilities. She didn't even skip a beat when she deduced that she would rank Stefani as the best. Corden then interjected when she briefly paused to consider her options, "Either way, this ends in a text message from someone." Keys added, "Well, one of them don't have my number. I'll just put him last." She continued with a laugh, "Gwen Stefani is best, Adam Levine is second and Blake Shelton is the worst. I'm not eating none of this, no!"
In an interview with Harper's Bazaar in 2017, Keys spoke about her time on The Voice. She even spoke about artist Chris Blue, who was on her team and ultimately won the competition on Season 12. "My artist Chris Blue is just incredible. He has taken the show and really shown what a real artist he is and how incredible he is to be able to handle the pressure and energy and all the crazy mix and just shine every time," she said about the performer. "He has really shown who he is, and he has evolved and come to a place where all of us would hope to get to, on a platform like this. I'm just taking it. I'm in gratitude, I'm excited."
Even though Keys has only served as a coach for three seasons, she told Harper's Bazaar that she learned a lot during her tenure on the show. "What I just continue to remember is that we all have the ability for greatness and all we have to do is believe it, and want it, and know that we deserve it," the "Girl on Fire" singer said. "And then, we can do it. Anything. Really, just that simple and just that hard. So if there's anything that I've been reminded of, and just talked about and shared, it's success."