Simon Cowell has issued a stark warning to this year’s The X Factor hopefuls, saying that even winning the show doesn’t guarantee a successful career.

Speaking to The Sun, the mogul said that anyone who does win the series only has a one in two chance of achieving long-term chart success.

“We can’t guarantee that they will be an international star,” Cowell said. “There is a 50/50 chance that they are going to make it. Sometimes it doesn’t work.

“The music business is hard. Trying to find a star with long-term appeal is not an easy job. But they will have a better chance of being a star after appearing on this show.”

The show has of course had its success stories – Leona Lewis has become a huge star around the world while last year’s winner Alexandra Burke is also tipped for global fame having signed a five-album deal in the US worth around £3m.

Burke has also been working with several renowned US producers and performers on her debut album, set for release in October.

However two of the five series winners so far – Steve Brookstein and Leon Jackson – flopped, while series two winner Shayne Ward has been only moderately successful in the charts.

“We don’t always get it right” Cowell admitted.

“People can give an amazing performance on the show but then they can’t get the whole career thing right. It’s disappointing but it’s out of our hands – it comes down to the public whether or not they like them after the show.

“But I’m 100 per cent committed to the artists.”