The former design instructor revealed to Parade that he never expected the phrase to become so popular with Project Runway fans.
"It's music to my ears. I love hearing it," he joked to the magazine. "I started to say it on the Project Runway set in the workroom only because it's what I said for years in my classrooms. I didn't know it would come out as a catchphrase."
Gunn also offered some holiday style tips for women, telling the magazine: "I used to always celebrate and praise the little black dress, but I have a different take this season. I want people to step out of their comfort zone and look at all the gorgeous colours and prints that are out there in party dresses."
He continued: "There's tons of sparkle and everything's affordable. There's no reason to leave your budget when you're shopping for party dresses.
"I've been doing a lot of it recently for various women I'm working with and I'm saying with seriousness that the most expensive item is $119 (£77), so I know it can be done."
Gunn also confirmed that Project Runway will return for a tenth season.
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