Some might say Sharon Osbourne, Nicole Scherzinger, Gary Barlow and Louis Walsh are the X-Factor judges.
But let's face it...the great British public are the real judges.
They are glued to the show week after week, they tweet about it in their masses and give up their hard earned cash to vote for their favourite.
Review: X Factor Live
So we asked some fans' of the show what they thought of tonight's live performance.
Kirsty Miller, from Bishopbriggs, said: "It was fantastic. Nicholas and Luke were the best. When Nicholas sang In the Arms' of the Angel...I had a wee tear in my eye. My mum (Jeanie) died and that song reminds me of her. It was her birthday today so it made it extra special for me."
Hannah Barrett was a favourite for Laura Carberry, from Kirkintilloch, who said, "I would have loved the crowd to be even louder for Nicholas...it is his homecoming gig after all."
But Elaine McGuire, from Bishopbriggs, disagreed: "The atmosphere has just been brilliant. Luke Friend was a surprise for me...he really got the crowd going when he ran out into the audience." Show opener Tamera Forster didn't make a big impression on Michelle Reston from Bishopbriggs who said: "She didn't hit the high notes for me."
Another disappointed fan was Jacqui Jones from Burnside who said: "I am a bit disappointed because there had been no narration throughout just video clips. None of the acts didn't even bother to say hello until the fourth song. I just felt there was no connection."
Mum-of-two Lisa Wilson, of Ayr, took her kids Elliot (6) and Olivia (9) to a meet and greet before the show. She said: "The show has been brilliant and they were so nice when we met them earlier."