X Factor winners; they seem so lovely, innocent and genuine before they triumph in their respective finals, but once they're crowned champions, you can't stop them mouthing each other off, The Mirror reports. 

We've basically made that rule up, based on what's happening between Matt Cardle and current winner, James Arthur. They seem to be arguing in public, ether saying one's not very good, or that they're more successful than each other. Both pretty distasteful and petty, if you ask us, which you didn't. But there you go.  When Arthur, the current winner of The X-Factor, who's destined to make a below average album with some awful dubstep/indie fusion - said that, "the blokes that have won before have had a niche, they haven't sold records because they haven't made great albums. That's the bottom line."

And Matt wasn't happy. He replied, saying, "I said, 'Look, James, you're very talented but you haven't sold two million records yet, which I have,'" Matt said, humbly taking his Mother Theresa costume out of the wardrobe and pulling it on while recounting a conversation which may or may not have taken place in his head. "You haven't had two top ten albums yet, which I've had. Don't start mouthing off before you've even really left the show."

Here at Contact Music, we don't want to put a downer on anything, but considering James Arthur has only really sung other people's songs, and that Matt Cardle's career has descended into mediocrity (at best), then all the pair are doing is reminding us of that fact. Jahmene, on the other hand, is loving life after signing a deal with Sony, and not slagging anyone off.