Cowell's signature phrase, "I don't mean to be rude, but …", was usually inevitably followed by an unsparingly blunt appraisal of the contestant's talents, personality, or physical appearance.
But when it comes to living up to its title — creating a superstar act that captures the imagination of millions — the power of "Idol" has been ebbing for years. (The new season of "Idol" starts Tuesday night (8 p.m. EST.) While the show produced multiplatinum sensations in its earlier days, starting with Kelly Clarkson and ending with Carrie Underwood, recent "Idol" winners or runners-up have not had similar chart success.
Kris Allen, last year's champion, has sold about 200,000 copies of his debut album. And while his "Idol" runner-up, Adam Lambert, provedto be more popular and controversial, even his debut hasn't stayed at the top of the charts for long.
"When you start thinking about 'American Idol' as a place that feeds the music business, it's not as much as people think it is," said Howard Benson, who produced the first two CDs for "Idol"-finalist Chris Daughtry's multiplatinum band, Daughtry. "It's fallen off."
Of course, "fallen off" is all relative when you're talking about a show that's been the undisputed ratings champion since it debuted in 2003. It has produced millions and millions in albums sales, Grammy Awards and even an Oscar winner in Jennifer Hudson, who is also a Grammy winner and successful recording artist. Even the also-rans of "Idol" have managed to parlay career success after an "Idol" stint.
"It is by far still the most watched show on TV — even more watched in some years than the Academy Awards and the Grammys or anything like that" says Ann Donahue, senior editor at Billboard magazine. "But actually translating those people who watch the show into buying albums remains difficult.
Like the rest of the music industry, "Idol" is battling a decline in music sales. But even taking that into account, the drop-off in sales and buzz for "Idol" winners is telling. When Clarkson became the show's first winner in 2003, her album, "Thankful," debuted at No. 1 and sold a healthy 297,000 copies, and had hits like "A Moment Like This" and "Miss Independent." It went on to sell 2.7 million copies, according to Nielsen SoundScan.
The next year, champ Ruben Studdard sold 1.8 million and had the hit "Sorry 2004." Clay Aiken, that year's runner-up, did even better, selling 2.7 million copies of his CD, "Measure of a Man."
Studdard was followed by Fantasia, whose "Free Yourself" also sold 1.8 million and had the R&B hit "Free Yourself." Underwood established herself as the show's most successful winner — her country debut sold nearly 7 million copies with major crossover hits like "Jesus Take the Wheel" and "Before He Cheats."
But the next winner, Taylor Hicks, was a major disappointment, selling 700,000 copies of his self-titled debut. Jordin Sparks followed with a platinum self-titled debut CD and hit songs, while David Cook had a platinum CD, also self-titled but without the hits.
This year, "Idol" champ Kris Allen released his self-titled CD to little fanfare. It didn't debut at the top of the charts and now sits at No. 91 on Billboard's Hot 200 albums chart and hasn't generated a top hit thus far.
In a recent interview, Underwood said being on "Idol" is not a guarantee of success, even if you have a hit debut.
"You look at people who came before me, too, like some of them you haven't really heard from in awhile. And I don't think it's just since me. I think you've got to have a lot of luck on your side, too. Just because people vote for you doesn't mean they'll go out and buy your album, and especially now," she said.
"You know you look at the music industry and all the changes it's gone through in the past five years, I don't know, it's just maybe in a different way they are successful, but they're just not selling the numbers because nobody's selling the numbers they did five, six years ago."
Still, the success of "Britain's Got Talent" finalist Susan Boyle shows if an artist piques the interest of America, they can still generate huge sales. Boyle's debut CD, "I Dreamed a Dream," has sold more than 3 million copies since it was released in November (the same month that Allen and Lambert's CDs were released). Boyle's CD was produced by a judge on "Britain's Got Talent" — the judge being Simon Cowell.
In an interview with Fox News, Cowell said he decided to leave the show after this season because "I don't think you should be doing the same thing over and over again."
"I hope and believe it's still the No. 1 show in America, which is a pretty good place to be. I think in a way it's a good thing for the show because it breaks it up you know it'll be speculation as to who's going to replace me and more shows need that," he said. "You can't have the same people the whole time, it gets boring."
"Idol" has already provided the show with some jolts. Last year, it added a fourth judge, Kara DioGuardi, to the original panel of Cowell, Randy Jackson and Paula Abdul, and last year, Abdul announced her departure and is being replaced by sunny talk-show host Ellen DeGeneres.
Donahue says contestants like Allen did well in digital downloads of their show performances, and that may be the best way to gauge their success since the show is more popular with the 18-to-49-year-old demographic, who tend to buy singles more than CDs.
"More and more we can expect 'Idols' do pretty well in terms of their digital downloads … but maybe it's not really a fair measurement anymore to see how they do in albums, because the people who watch the show, who buy music, buy singles, they don't buy albums," she said.
Fantasia, who had a gold CD and success on Broadway after her initial success, said in the end, the success or failure of any "Idol" depends on the winner — and not "Idol."
"It's in your hands. We had to fight for (our success) as well. … You have to make sure you put out great music and sell yourself," she said.
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