Which Celebrity Judge Is The Odd One Out?

Who didn't get the call from Simon?

CORRECTION

Aug. 06, 2017, at 21:34 PM

Alesha Dixon has been a judge on Britain's Got Talent and is currently filling in for Sharon Osbourne at the 2017 X Factor auditions. An earlier version of this post said that Alesha hadn't been on X Factor and was a judge on America's Got Talent.