"Britney is quite mean, which I think you will discover," said Cowell.
The 52-year-old who is known for giving tough comments himself, says that Spears and fellow judge Demi Lovato are harder to please than him or fourth judge singer L A Reid, reports femalefirst.co.uk.
"They are harder to please than me or L.A. They are very happy giving people a no. They definitely have their own opinions," he said.