Watch the full interview with Simon Cowell on Tuesday night. "Piers Morgan Tonight" airs weeknights on CNN/US at 9 p.m. ET and on CNN International at 0200 GMT (live simulcast), 1200 GMT and 2000 GMT / HKT 1900.
CNN -- Simon Cowell, gearing up for Wednesday's premiere of "The X Factor" on Fox, told CNN's Piers Morgan, "It is the biggest moment in my career."
The creator, executive producer, and judge on the new vocal competition series is a guest on Tuesday's "Piers Morgan Tonight."
Morgan asked Cowell how the American version of "X Factor" differs from the UK version, which has dominated British television for eight seasons.
"It has its own personality," said Cowell. "When I watched it back at this screening we did, I got a real buzz."
Cowell, who also created "America's Got Talent" -- for which Morgan serves as a judge -- told Morgan that the talent on "X Factor" is "crazily good."
Cowell cautioned, however, that "there's a long way to go. And I've seen people who start off great and then for whatever reason, if you put them on the live show, they're horrendous. ... But so far, I'm happy."
When he left "American Idol" in 2010 after nine seasons as a judge, Cowell also walked away from over $100 million he could have been paid for staying put. He also invested a great deal of his own money into "X Factor." In addition, the "X Factor" prize money is an unprecedented $5 million recording contract.
"There's a lot at stake here, isn't there, for you?" asked Morgan.
"You don't go into anything contemplating failure," said Cowell, "because if you did, you wouldn't make it. If it didn't work out well, I would be really, really upset, disappointed, because I believe in it. I believe in the show, I've done the show for a long time, I do think it's the best one. I actually do. And when it works, it's fantastic. But you have to be a big boy about these things, you know? And you've got to take risks. And part of what I've loved about doing this is the risk I've taken."
Cowell told Morgan that put his "heart and soul" into "X Factor," and pointed out some of the program's other distinguishing characteristics.
"I like the fact that there isn't an age limit," said Cowell. "You're going to see a very different type of contestant."
Cowell told Morgan that when the rules for "X Factor" were created, they made the minimum audition age 12 and set no upper age limit whatsoever.
"Or you could be in a group," Cowell pointed out. "We also kind of said it has to reflect what is happening in the music business, this show. And in the music business, a lot of people who are having hit records, they've gone through similar issues. They've had drug problems, alcohol problems, home problems -- you name it, they've had them.
"And they've normally used this to sort themselves out. And so I absolutely felt the same way. I didn't want to start putting too many rules on it. It was all about talent. Somebody wants to make their life better, they own up to what they did; I don't have an issue with that. And I had no qualms showing it."
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