Papa John's Founder, Chairman and CEO John Schnatter takes celebrating the opening of his 4,000th store in New York's Times Square. (Diane Bondareff/INVISION FOR PAPA JOHN'S INTERNATIONAL)

During a recent trip in the British Isles, John Schnatter, the founder and face of Papa John’s, stayed in an old castle-turned-resort in Ireland. Impressed by the architecture and beautiful grounds, he asked the manager why there weren’t more castles in the region that had been converted into hotels.

The manager’s response: “All the laborers, all the peasants and farmers, they burned all the castles down.” So why hadn’t the workers burned this one down, Schnatter asked.

“He was a fair landlord,” the manager replied. “He took care of his people.”

Schnatter told the story to a room full of entrepreneurs gathered in Washington on Thursday for National Small Business Week, sharing what he says is one of the most important lessons for small business owners.

“If you don’t care of the people who are doing the heavy lifting, they will burn your castle down,” he said. He later noted that he doesn’t let him to get a bonus at the end of the year unless his employees, from the managers in the stores to the janitors at his headquarters, get one, too.

“If there’s one thing you remember from tonight, take care of them,” he said.

Here are three other pieces of advice Schnatter shared during the event.

Stay nimble

Often, Schnatter says, companies establish a business plan or settle on a budget for the year, and “then become inflexible.” It’s that rigid mindset that keeps those firms from innovating and solving problems as quickly as possible.

“If we get new data, we change on a dime,” he said.

Right now, for example, the company is adopting a new routing system for its delivery trucks and looking at ways to monitor the condition and temperature of ingredients while they are in route to the stores. If new data suggests “we’re going in some wrong direction, we’re not going to just ignore that,” he added.

Despite its success in the marketing arena, Schnatter said the company is currently overhauling its advertising strategy, too.

“Sometimes, you have to get rid of something that’s good to take a chance on something being better,” he said.

Do what you love

Above all else, Schnatter said, the key to business success is identifying something that you’re naturally good at — even if that means a ton of trial and error.

“All of us have a gift,” he said. “Bounce around until you find it.”

He went on, noting that “the woman that cuts my hair, she loves cutting hair. My orthodontist, he loves fixing teeth. Peyton Manning, at three years old, loved throwing a football. Find something that’s intuitive, something that’s instinctive, something you just love to do.”

But don’t overstep your limits

During the event, one attendee asked Schnatter whether Papa John’s was having any success in the birthplace of pizza — Italy.

“We’re not in Italy,” Schnatter responded with a grin. “I learned how to make pizza from a real Italian, sure, but you know, a man’s got to know his limitations.”

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