So I don't watch the show but comments on FB got me intrigued enough to google and then watch the clip.
I'm sure she thinks her prank was hilarious and that Simon Cowell deserved it, but regardless she took the limelight and attention off the people performing their act - which was potentially one of the biggest and most important moments of their life.
For what? ... Nothing.
Aibu to think she is just a selfish and immature woman?