In hindsight, Leona Lewis' 2007 debut albumwhich went on to break more pop records than a rhino set free in Sam Goody, can be considered an unfortunate prophesy of sorts — like its titular Spirit, the LP initially drew disciples far and wide, but Lewis, not long after, faded into the ether.

So, 10 years after the height of Lewis' peak popularity, we're forced to ask: Why didn't she last?

Like Kelly Clarkson before her, Lewis captivated a nation of big voice-loving TV viewers with consistent weekly performances on the United Kingdom's X Factor, and secured her eventual Season 3 victory with a teary rendition of "A Moment Like This." And her 2006 win immediately set into motion the biggest act the show had produced: Then 21, Lewis watched her single shoot to No. 1 on the U.K. singles chart and break the world record for most digital downloads within 30 minutes at 50,000.

And that was just the beginning. Simon Cowell's beloved mentee —the first woman to win the X Factor prize — immediately proved the show could genuinely dispense international success, American audiences included. Beyond the fact that Spirit, Lewis' debut 2007 album, went platinum TEN TIMES OVER in her home country (it was also eventually named the fourth-best selling album of the decade, and remains the best-selling debut album by a female artist ever), it debuted at No. 1 in nine countries, including the United States. Lewis was, in fact, the very first British act to reach No. 1 with a debut album in the United States, proving Britney and Christina could get real-time competition from overseas.

And that's before the explicit mention of "Bleeding Love," the album's lead single, which proceeded to top the charts in 36 countries (it followed Elton John's "Candle in the Wind" as only the second song to achieve the feat). "Bleeding Love" became the best-selling single of 2008 worldwide and was the No. 1 digital song in the United States in 2008 (it was second only to Flo Rida's "Low" overall). The single also earned Lewis three Grammy nominations, and her vocal talent and expert balladry proved to be just as critically renowned as commercially successful.

Sarah Rodman of The Boston Globe noted of Spirit: "The tracks are impeccably manicured, super-tuneful, and offer lyrics about the various agonies and ecstasies of love that are unremarkable in and of themselves but reach nuclear-threat levels of desperation thanks to Lewis's voice."

But was her voice big enough to last? The performance of Lewis' second album — and what came after — said something to the contrary. By the time "Bleeding Love" had run its course, Lewis had officially released her only track that would ever crack the Billboard 100's Top 10.

Echo, released in 2009, achieved moderate success, but even by recreating "Bleeding Love" magic with the help of Ryan Tedder, Lewis and her lead single "Happy" only hit No. 31 on the Hot 100, and follow-up "I Got You" didn't chart at all. And by the time Lewis released 2012's dubstep-leaning Glassheart, she had become a mostly faded pop-memory in the States. Sure, her Afrojack remix of "Collide" with Avicii was a niche dance hit, but it was a far cry from "Bleeding Love."

Where the United Kingdom audience was concerned, though, Lewis still managed to score a Top 10 hit with "Trouble."

In June 2014, Lewis announced that she had parted ways with her label of seven years, Syco Music, effectively ending her relationship with Cowell. And while I Am, her fifth studio album, was the product of her sincerest efforts to date, she insisted, it did little to impact charts. It debuted at No. 12 in the United Kingdom's charts in 2015 having sold only 24,000 copies, and singles "Fire Under My Feet," "Thunder" and "I Am" landed with deafening silence.

So why was Lewis' fall from grace so pronounced? Well, one theory is that she's never been able to ditch her reputation of being too meek to be sustainably interesting, and that the standing-and-belting-out-a-ballad routine could only entertain audiences for so long. While she has a lion's voice, she's rarely demonstrated tantamount grit, and critics and audiences have noticed. Even Leona admitted to being a bit withholding during a 2011 interview with The Sun

"I’d rather be seen as boring than a harsh, brash person. It doesn’t bother me," she said.

Others say the bulk of Lewis' material from her second album onward never lived up to "Bleeding Love," and that she should've taken more risks.

"Leona’s 'Happy,' however, was just a poor man’s 'Bleeding Love,' a message to the casual, one-album-a-year brigade that they needn’t bother with the new record because it’s more or less the same as the one they’ve already got," Michael Cragg of The Guardian wrote in 2015. "Echo sent her on a UK arena tour, but it felt like it was happening off the back of that one single."

By all accounts, Lewis is still a perfectly adept artist, and the performance of her work since Spirit is nothing to sneeze at. Still, to watch her fade as if Mariah Carey had vanished after Mariah, or Clarkson disappeared after Breakaway just seems inexplicable. And still, somehow, someone like Generation Z standout Danielle "Bhad Bhabie" Bregoli only knows Lewis as that singer of "old R&B music."

At the very least, we'll always have "Bleeding Love."

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