When supermodel Iman was at the height of her career in the fashion industry, she did something no one expected: She retired.

It was an abrupt move, but it's also one that Iman has stood by faithfully for decades -- in fact, she hasn't attended a single fashion show in 26 years. Speaking with "Oprah: Where Are They Now?", the former model explained exactly why she stepped off the catwalk and didn't look back.

"I was just starting to create Iman Cosmetics , so I wanted to be also taken seriously and not be at fashion shows every day," she begins.

Then came the final nail in that coffin.

"I read they held a show -- an hour -- for Paris Hilton," Iman says. "I knew the game had changed. It became where everybody wants to be seen."

Not only that, but the tight circle that enclosed fashion's elite seemed to be widening to the point where it was becoming nonexistent.

"I mean, when you have D-listers... We're not talking about Linda Fargo from Bergdorf Goodman. You know, you hold a show for that person because she is the establishment, she is fashion," Iman says. "But, seriously? Paris Hilton? No."

"Oprah: Where Are They Now?" airs Saturdays at 10 p.m. ET on OWN.

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