"This is The Voice!" Such is the mini-theme song that plays briefly at the end of every commercial break for NBC's hit singing competition seriesThe Voice, successfully setting the scene.

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One of the major draws for The Voice is the fact that the musicians who judge the competition are also the ones who coach it! This means that the singers involved end up doing a lot more for the contestants than Simon Cowell ever managed to do on American Idol. As with most things, though, some coaches are vastly more talented when those chairs spin around than others.

Best: Alicia Keys

Coach on NBC singing show

One of the key metrics involved in this list is the idea that winning competitions does not necessarily make the coaches better. Sometimes, coaching goes a lot further than winning.

In this case, though, Alicia Keys makes the list because she was a solid coach and a fantastic winner. On the vocal talents of Chris Blue in season twelve, Keys won her first and only title as a coach on The Voice. She also competed in two other seasons and was always an effective leader.

Worst: Gwen Stefani

Gwen Stefani: The Voice Coach 2019

The main problem with Gwen Stefani as a coach for The Voice is the fact that she never sticks around long enough to make a difference. Instead, Stefani has served as a plug-and-play coach whenever NBC needs a singer to fill in for a season.

Stefani has racked up five tenures, but none are consecutive and none have ever amounted to victory. She's never even finished in the top three! Stefani may be a solid role player, but she's one of the worst Voice coaches.

Best: John Legend

The Voice coaches

When John Legend isn't crooning on holiday specials or fighting for justice in the world, he's making a name for himself as one of the best coaches in the history of The Voice. His biggest claim to fame came when he coached Maelyn Jarmon to victory in spring 2019.

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Legend is known for his controversial reluctance to turn his chair. But sometimes, quality over quantity pays off. In terms of coaches with impeccable ears, John Legend might just rank first.

Worst: Usher

The Voice contestant winner

Speaking of instances where victories don't make the coach, this is definitely true for Usher, who won in season six with Josh Kaufman. That's all well and good, but at a certain point, the talents of the contestant do a lot more than the coaching prowess.

This is absolutely true for Usher, an artist who is perfectly fine but lacks the discipline that sets true Voice geniuses apart from the pack. Usher's point of view was very rarely engaging and his presence on the series was largely dull.

Best: Nick Jonas

Jonas Brothers coach The Voice

So far, Nick Jonas has only coached one season on The Voice (he's due back for another in the spring), but in that arc, he made it clear that he's an exceptionally talented coach. He coached both Allegra Miles and Thunderstorm Artis to solid finishes, even if they were outside the top two.

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In addition to this, Nick always had insightful critiques and clearly took the job very seriously. He took notes and carefully observed every nuance and used his steals perfectly. The Jonas Brothers are naturals in the music world and Nick is a natural on The Voice.

Worst: Miley Cyrus

The Voice big red chair peace sign

Miley Cyrus was only a member of the team on The Voice for seasons eleven and thirteen, but in that time, she left little to no impact on the series or her contestants.

It's not necessarily Miley's fault. Sometimes, singers just aren't good matches for The Voice. Ultimately, her chemistry was lacking and her coaching abilities just weren't up to par for the dominance of others on The Voice.

Best: Adam Levine

Adam Levine on The Voice

One would be pretty hard-pressed to coach on The Voice in each of its first sixteen seasons and not make a name for himself as one of the best coaches. Fortunately, Adam Levine's early coaching career makes up for his steady decline in effort towards the end of his run.

No matter what, though, Levine always cared. He knew the show was a lot of pomp and fluff, but he always did the best he could for the singers who had dreams. He won the show three times, in seasons one, five, and nine, showing the longevity required to span a half-decade of The Voice.

Worst: Blake Shelton

Blake Shelton sitting in a red chair on The Voice

Conversely, Blake Shelton has been the singular mainstay for all nineteen seasons (and counting) of The Voice. Yet, in that time, he has yet to prove himself as anything more than a country singer with a fan base.

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Shelton has won the competition with singers seven times, which is a staggering figure. However, one could easily argue that he hardly deserved some of these wins, especially the most recent pull by Todd Tilghman. Ultimately, Shelton is a champion because his audience overlaps with the audience of The Voice. But his lack of coaching expertise does not cancel out his experience.

Best: Kelly Clarkson

Kelly Clarkson on The Voice season 19 as a coach

One of the best decisions The Voice ever made was to bring Kelly Clarkson into the mix. She has quickly proven herself to be the show's best coach, largely because of her own experience with the singing competition format.

Clarkson has been so deft that she has managed to take over Levine's spot on the stage while also running her own talk show. In her first two seasons on the show, Kelly won both times before winning again in her fourth season. On top of this, she always goes the extra mile for her contestants in a post-Voice landscape. Kelly is the best coach and there's not a close second.

Worst: CeeLo Green

Season one Voice coach

Conversely, the obvious choice for the worst coach is CeeLo Green. He was one of the original coaches on The Voice, but in spite of his four seasons on the show, he never managed to coach a champion.

On top of this, CeeLo comes back to the show for musical medleys with the other coaches, as if he's some beloved institutional figure on the show, but he really hasn't done very much.

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