As the host of CNBC's "The Profit," Marcus Lemonis dispenses business advice to struggling entrepreneurs every Tuesday night. Lemonis is a self-made multimillionaire and CEO of the billion-dollar company Camping World. On "The Profit," Lemonis regularly teams up with small business owners who need his help turning around their businesses. In 2018, Lemonis dispensed plenty of helpful advice for aspiring entrepreneurs, both on TV and in interviews with CNBC Make It. Here's some of the best advice Lemonis offered up over the past year:

Narcissism is bad for business

A small business owner's narcissism was at the heart of an episode of "The Profit" that aired in July 2018. "I hadn't dealt with a narcissist to this degree," Lemonis said about Dino Pavoni, the owner of Simply Slices, a family-run drive-through pizza chain in the suburbs of Chicago that appeared on the show. "If he doesn't learn to trust other people, particularly his family, his business will be the same forever," . In the episode, Pavoni sought out Lemonis' help with growing his business, but Pavoni's attitude ended up turning Lemonis off.



Pavoni may be his own worst enemy — he's controlling and disrespectful — and, that's a recipe for failure when you're the boss, according to Lemonis. In the end, the entrepreneur's controlling attitude and inability to take feedback left Lemonis unconvinced that Simply Slices could grow into a nationwide chain.



"If Dino can't even take feedback, or have a discussion with his son or an employee, how's he going to take feedback from a franchisee that's four states away?" Lemonis asks in the episode.

It's never too soon to learn a strong work ethic

Growing up in Florida, Lemonis says his family ruled with an "iron fist" in terms of making sure he learned the value of a solid work ethic at a young age. "I started my business career as a teenager and my family ruled with an iron fist," Lemonis tells CNBC Make It.



Lemonis' family put him to work at the family business at a young age, often at the expense of typical teen activities like going to summer camp, playing Little League Baseball or even going on school field trips, he says.



Working hard "was ingrained in the culture of our family," Lemonis says. But it helped him establish a very strong work ethic. Lemonis grew up around his own family's business, a Miami-based automotive dealership owned by his grandfather, Anthony Abraham. Along with working at the family business, where he says he learned "positive and prosperous business values," Lemonis also became an entrepreneur at an early age. At 12, Lemonis started a lawn-mowing service in order to make enough money to start another business selling candy with his friends.



Of course, Lemonis admits now that spending less time working and more time with kids his own age might have helped him develop better social skills at an early age. But, he still believes that developing his work ethic early on helped him succeed in business. "It was good because I was able to learn how to adapt in adult environments, learn how to communicate with adults, learn how to integrate in a business environment," he says.

Always know who you're working with