Prior to 2011, the Grammy Award for Best New Artist had never been given to a jazz performer. But that all changed when Austin-based jazz bassist and singer Esperanza Spalding stunned everyone, including herself, by taking home the trophy.

A broad contingent of Spalding’s fans, especially within but certainly not limited to the jazz community, knew she possessed winning musicianship. But few believed she had even a puncher’s chance at the actual award. Especially for its highest-profile categories, the Grammys tend to reward top-selling acts signed to major record labels, regardless of musical merit. And with teenage heartthrob Justin Bieber in the running — not to mention Drake, Florence and the Machine, and Mumford and Sons — her missing out seemed a foregone conclusion.

Consider this: Spalding’s most recent album at the time, the string-soaked, independently released Chamber Music Society, received zero Grammy nominations — and just as much airplay on commercial radio. Much of the mainstream pop audience, which heard her name for the first time at the ceremony, surely thought: Esperanza who? (One angry Justin Bieber fan vandalized Spalding’s Wikipedia entry by writing, among other things, “WHO THE HECK ARE YOU ANYWAY?”)

The easy answer is that she’s a highly skilled and marketable musician. She’s obviously photogenic and preternaturally poised in the spotlight, be it performing for Barack Obama three times during his presidency (twice at the White House, once at the Nobel Peace Prize ceremony), headlining sold-out shows across North America and Europe, opening for Prince, co-hosting the Grammy pre-telecast ceremony or receiving a Grammy herself. Her youth and virtuosic talent make her a natural spokesperson for an American art form.

Predictably, Twitter blew up following the announcement, with jazz aficionados unable to conceal their delight. Bassist Philip Booth wrote, “OMG moment of the #Grammys: A bona-fide jazz musician, superb bassist and singer won Best New Artist!” Vocalist Diana Reeves added, “Esperanza won best artist because she truly is!” No telling if critic Nate Chinen followed up on his tweet, sent just before the winner was announced: “If Esperanza wins this, I’ll go out and make a snow angel, naked.”

True, the Grammy for Best New Artist has often been the subject of criticism. Some years the winner seems too shallow, based on popularity more than artistic merit, like when Macklemore and Ryan Lewis beat the likes of Kendrick Lamar, James Blake and future multiple Grammy winners Kacey Musgraves and Ed Sheeran. Other years it seems like the Grammys are oblivious to success and just go for the most “Grammy-friendly” act in the lineup, which usually means avoiding hip-hop and EDM, like when Bon Iver beat J. Cole, Nicki Minaj and Skrillex. But Spalding’s win remains the biggest Best New Artist upset ever.

Spalding was no stranger to praise; she got a scholarship to attend the prestigious Berklee College of Music and received praise from Obama and Pat Metheny well before her historic win. So her nomination wasn’t a total shock, even though her name wasn’t familiar to most. But it definitely was a shock when Jewel and John Legend announced her name as the winner on Grammy night.

It’s especially surprising in hindsight since Spalding’s competitors were a who’s who of soon-to-be superstars. Any of the four competitors would have been traditional Grammy choices.

That said, Spalding’s win was nothing short of great. It looked as if front runner Bieber was slightly upset (who could blame him?). Drake seemed pleasantly surprised, while Florence and Mumford both cheered on the jazz prodigy’s unexpected win, while Spalding herself walked confidently to the stage (after mouthing an understandable “Oh my God!”) and gave a graceful speech, dedicating the award to the people who’d helped her get where she was, as well as the “incredible” music community.

That last point may reveal why Spalding managed to pull off such an odd victory. A lot of people forget that Grammy voters are musicians, songwriters, producers and other industry insiders, the kinds of professionals likely to cherish a success story like Spalding’s and who love to see that kind of talent recognized. Being such a prodigious musician may have resonated with voters more than Bieber’s teen music or Mumford and Sons’ indie folk rock.

Spalding represented the underdogs, the instrumentalists, composers, performers who may not have gotten the stardom but have passion and dedication for their craft. Wins like Spalding’s show that, despite the still-prevalent criticisms of their voting process, the Grammys sometimes do acknowledge artistry over pure hype.

Spalding closed her speech by promising to make “a lot of great music,” and she kept her word, racking up four more Grammys since her BNA win, including Best Jazz Vocal Album last year for 12 Little Spells, while remaining a prestigious name. And needless to say, the other nominees seem to be doing okay for themselves, too, with two quite literally ranking among the most successful artists of the past 50 years (Bieber and Drake) and three of them eventually becoming Grammy winners (Bieber, Drake and Mumford and Sons).