Before appearing on Shark Tank together, Spanx founder Sara Blakely and investor Kevin O’Leary were on a business panel.

This week, Blakely posted the throwback video on Instagram and explained why she still believes what she said 12 years ago at a CNBC Town Hall Event called “Getting Back to Business.”

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In the clip, O’Leary says he goes to battle with the competition and takes an aggressive approach, saying, “Business is war.”

“You get up in the morning and you figure out how do I kill my competitor?” O’Leary said. “How do I pour boiling oil on them? Competing, winning, fighting, winning, competing.”

Blakely disagreed, but despite launching Spanx in 2000 at the age of 27 with $5,000 in savings and turning it into a billion-dollar company by 2012, she says she was nervous to speak up, especially to Mr. Wonderful.

“I’ve done it very differently,” she said. “I have not been obsessed or focused on the competition and annihilating the competition. I have only been focused on my own quality. What can I offer that’s the best and give value?”

The pushback paid off. Spanx is currently one of the largest direct-to-consumer brands in the world. Blakely was a guest investor on Shark Tank in 2017 and has been back multiple times, even sitting next to O’Leary, who has been a Shark Tank judge since 2009.

^{Sara Blakely and Kevin O’Leary. Credit: Eric McCandless via Getty Images}

Blakely says she still stands by her words today, and obsessing over the competition is the wrong approach.

“I truly don’t believe business is war,” she said. “I think that you should be focused on your consumer, what you can do better for your consumer, how you can give them a better experience, a better product.”

“Be genuine, be authentic with what you’re creating for them, and give back,” she added. “What about that feels like a war?”

Investment fund Blackstone bought a majority stake in Spanx in 2021 at a valuation of $1.2 billion. Blakely is now worth an estimated $1.3 billion.

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