Marcus Lemonis has seen his fair share of companies come and go on his showThe Profit. Some of the people he meets just shouldn't be in business, he told attendees at last month's Inc. 5000 conference.

How can Lemonis waltz into a business he knows nothing about and give advice? "It's very simple," he says. "I just go do the job for a while. I know I'm going to absolutely suck at it, but the level of respect and camaraderie it builds--you can't put a price on that."

Business comes down to three key principles for Lemonis: people, product, and process.

Watch the video below for more on these three principles and how to avoid becoming an ivory tower manager.