Speaking to Oprah Winfrey on her Master Class show, the 51-year-old music mogul recalled being kicked out of a meeting with an unknown network executive while trying to sell the singing competition with then-partners Simon Fuller and Simon Jones.
"It was so bad that a minute into the pitch the guy said 'No'. To wind him up, I said, 'So, it sounds like you’re interested?' He said 'Get out' and we were thrown out of the network.
"I turned to the other Simons and said, 'The good news is, it will never get worse than this'... [I left with] my tail between my legs."
American Idol, which was eventually picked up by Fox and first aired in 2002, returned for its 10th season on Wednesday.
The latest edition is the first not to feature Cowell on the judging panel, after he quit to concentrate on launching a US version of The X Factor.