Before serial entrepreneur and fashion mogul Daymond John decides to hire someone, he makes sure to ask one curve ball question — and how the candidate responds tells him a lot about their mindset and work ethic.
At CNBC's iConic conference in New York, John told CNBC Make It that he always asks, "What's ever happened to you that was beyond your control after you were 15 years old?"
For the self-made millionaire who grew up in poverty, the right answer is simple: "Nothing."
"Unless there's a disease, there's really nothing beyond your control after age 15," he says. "Nothing is outside of your control, especially your career."
The question helps John weigh how a person views challenges and obstacles, which will inevitably arise over the course of one's life.
John, who was raised by his mother in a working-class neighborhood of Queens, New York, started working as a teenager. He launched his fashion line, FUBU, while still working a regular day at a full-time job.
"It was 40 hours at Red Lobster and six hours at FUBU," he says. "Then it was 30 hours at Red Lobster and 20 hours at FUBU, because money started to come in."
For him, excuses don't carry much weight.
"The key is to always show an investor, a potential boss and even yourself, that you have control over your future and are determined to work hard," John says. "You should never make excuses."
Nothing is outside of your control, especially your career.Daymond Johnserial entrepreneur and judge on "Shark Tank"
If you can understand and learn from your mistakes, you'll be smarter moving forward.
"If you're successful, it's not by luck," John says. "And if you may not have had the career that you would like, who else are you going to blame it on?"
Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."
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