Reality TV
Rex Features
The 2008 Britain's Got Talent winner has been released by the company amid reports of a falling out between Sampson and Cowell, the Daily Mail reports.
A source said: "George just didn't prove as marketable as Simon had hoped.
"When acts like George win the show, it's much harder for them to forge a successful and moneyspinning career compared with a singer, like Susan Boyle."
Sampson recently suggested that he and Cowell were not getting on and claimed that he owed money to Syco despite the success of his dancing DVD.
However, a Syco spokeswoman replied: "There is never a case where artists owe money and nor do marketing or promotion costs come from their percentage. In addition they also get an advance on projects."
Regarding Sampson's relationship with Cowell, she added: "They could work together again in the future. The door is very much open for any other projects that come up."
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