The 5 biggest mistakes small business owners make according to 'Shark Tank' stars

"Shark Tank" has changed the outlook for many small businesses over its eight years on the air. That makes its stars some of the most knowledgeable people on earth when it comes to what makes or breaks small businesses and why they're so important to the American economy.

"Small businesses are near and dear to my heart, both from the show and my personal experience," "Shark Tank" star Robert Herjavec recently told Business Insider.

In addition to his "Shark Tank" duties, Herjavec has spent about a year working with Deluxe Corporation on "The Small Business Revolution," which picks an American town and helps to turn around its local economy though supporting small businesses.

"I think that in America today, that is security: starting a business, being an entrepreneur is security," he said. "The idea of getting a job at a big company and retiring on a pension - that's long gone."

But that doesn't mean being an entrepreneur is easy. Business Insider asked Herjavec and his "Shark Tank" costars what they believe to be the biggest challenges small businesses grapple with on the path to success.

Here are five big mistakes small business owners make according to the "Shark Tank" stars: