One of the most successful 'Shark Tank' entrepreneurs shares the biggest lesson she learned in her 20s

Melissa Carbone scored big on "Shark Tank" in the show's fifth season when she made a $2 million deal with Mark Cuban in exchange for 20% of her horror attractions company, Ten Thirty One Productions.

Not only did she make one of the biggest deals in the show's history, but she's also been one of its most successful entrepreneurs.

Last year, Ten Thirty One brought in $3 million in revenue, and Carbone has plans for expanding her Haunted Hayride and other spooky events from Los Angeles to New York, San Francisco, and Atlanta.

She tells Business Insider that a crucial lesson she learned in her 20s has allowed her to be the CEO and president of a successful and rapidly growing company.

As a manager at Clear Channel, Carbone realized that she couldn't be a leader if she mulled over a decision for too long or continuously looked for counsel.

The lesson: "Use your best judgement and just make a decision," she says. "It may not always be the right one, but that's OK. A wrong decision is better than a demeanor of uncertainty."

"A good and swift decision-maker will gain the trust and buy-in from employees, business associates, and customers/clients because it will illustrate confidence," Carbone explains. "Decision-makers are leaders."