The world's biggest boy band, One Direction, was birthed from the X Factor; imagine if those five boys had never met on the program! It's important to note that 1D didn't win the contest: They placed third in the 2010 season, but found far more success than winner Matt Cardle or runner-up Rebecca Ferguson.
Did you know the biggest girl group in America was also birthed on the X Factor? Cowell brought together the five lovely ladies of Fifth Harmony on season 2 of the show, and although the group did not win, the quintet has achieved international success with hits like "Worth It" and "Sledgehammer."
Olly Murs auditioned for the X Factor in 2009: At that point in time, the Brit was just a regular 25-year-old working a dead end job. Murs didn't win the show, but his runner-up status helped him find real fame overseas, and in the U.S. with the Top 40 hit "Troublemaker."
Little Mix are one of the biggest girl groups in the world, and with good reason: Long before this year's Get Weird, the fearless foursome came together in 2011 on the X Factor. Unlike the other groups on this list, LM won the competition, becoming to first group to ever do so on the U.K. version of the show. Next stop: World domination!
Before Cher Lloyd was collaborating with the likes of Demi Lovato, T.I. and Becky G, she was just a young English teen with a big dream...and an uncanny ability to rap. She was eliminated after reaching the fourth spot in 2010 (one worse than One Direction), but went on to find real success outside of the show with hits like "Want U Back" and "With Ur Love." Her last album, Sorry I'm Late, debuted at No. 12 on the Billboard 200 chart.
Before she was "Bleeding Love," Leona Lewis was the very first winner of the British X Factor. Lewis won the competition in 2006 with a cover of Kelly Clarkson's "A Moment Like This." It was so freaking popular in the U.K., it broke a world record after being digitally downloaded more than 50,000 times in less than 30 minutes. Really!
The X Factor isn't all boy bands, people! Real pop-rock groups can make it too. Emblem3 finished fourth on the second season of U.S. X Factor, and in 2013 released its debut album, Nothing to Lose, before opening for Selena Gomez on tour. Originally a trio, Emblem3 is now down to two members following Drew Chadwick's departure, and is reportedly working on a new album for 2016.
Nothing like a kickass boy-girl duo, yeah? Alex & Sierra fill that void. The couple was mentored by Simon Cowell himself and actually won the final U.S. season of the show, becoming the only group to earn the American crown. The group's debut album, It's About Us, scored a Top 10 debut last year.