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

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

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

“You wake up in the morning and figure out how to kill my competitor?” O'Leary said. “How do I pour boiling oil on them? Compete, win, fight, win, compete.”

Blakely disagreed, but launched Spanx in 2000 nonetheless at the age of 27 with 5000 dollars in savings and returning it to a billion dollar company until 2012, she says was nervous to talk, especially about mr. Wonderful.

“I did it very differently,” she said. “I have not been obsessed or focused on competition and annihilating the competition. I have only focused on my quality. What can I offer that is the best and provides value?”

The vacation paid off. Spanx is currently one of the biggest direct to consumer brands in the world. Blakely was a guest investor on Shark Tank in 2017 and has returned several times, even sitting next to O'Leary, who has been a Shark Tank judge ever since 2009.

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

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

“I really don't believe that business is war,” she said. “I think you have to focus on your customer, what can you do better for your customer, how can you give them a better experience, a better product.”

“Be honest, be authentic with what you're creating for them and give back,” she added. “Does this feel like a fight?”

Blackstone Investment Fund buy majority stake in Spanx in 2021 at a valuation of $1.2 billion. Blakely is now valuable about 1.3 billion dollars.

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