Louis Walsh says girls in bands 'don't like each other' because they are always competing to be the 'lead girl' and want to 'be the skinniest'.
The Boyzone and Westlife manager joined Popstars: The Rivals in 2002, where the two final bands — Walsh's Girls Aloud and Pete Waterman's One True Voice — went on to compete for Christmas number one.
He thought he would get a boyband going into the show, and Kate Thornton asked him why he didn't want to manage girl bands and about his 'reluctance to manage female artists'.
Speaking on White Wine Question Time, he said: "Girls don't like each other in bands, it's very, very simple.
"Girls don't like each other. They all want to be the lead girl. They all want to go out with a footballer. They all want to be the skinniest."
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He remembered finding the hit Sound Of The Underground for Girls Aloud, and said Waterman had not really spoken to him since they went on to gain the coveted Christmas number one spot.
Walsh said he hadn't wanted to go on TV when he was first offered the role by one of the producers, saying he was 'very happy' managing bands.
"I was making good money as a manager," he told Thornton. "And then he offered me a load of money, and I just said yes.
"But then when I did Popstars: The Rivals. I thought I was gonna get the boy band. I was convinced. And they gave me the girls."
Walsh and Thornton also remembered their time on The X Factor, where Walsh was a judge for ten years from 2004 before a return in 2016.
Thornton said she, Simon Cowell, Sharon Osbourne and Walsh all had dressing rooms next to each other, describing the corridor as 'a little hotbed of action'.
Walsh replied: "If people knew what went on, that was the real show. That was fantastic. It was brilliant. And it was all real, everybody thought we were in who's getting voted on, what category, we didn't know anything.
"And that's what made the show so amazing. We took it so serious, and it was great. We had a brilliant time."
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