It's the first day on the job for new Starbucks CEO Brian Niccol, and expectations are high. 

The 50-year-old executive is taking over amid turbulent times for the coffee giant, which faces mounting pressure from activist investors, unionization efforts and sluggish sales in the U.S. and China, its two largest markets.

Niccol has a strong track record of turning around troubled companies: As CEO of Chipotle, he helped the chain rebound from its foodborne illness scandal and led its restaurants through the pandemic. 

Wall Street analysts have called Niccol — who served as CEO of Taco Bell before his six-year stint at Chipotle — a "dream hire" and a "hall of fame restaurant CEO."

Niccol attributes much of his success to a "cliché" piece of career advice he started following in his 20s: "Believe in yourself."

"I know it's a cliché, but you absolutely have to believe in yourself and have the grit to not give up, when it at first might not be going your way," Niccol said in a May 2024 commencement speech at Miami University in Oxford, Ohio. 

Niccol explained that he carries a "beat-up notebook" with him to outline and track his progress toward his career goals. "Whatever it is you need to do to keep yourself focused on your goal, do it, and believe you can do it," he added.

Trusting his gut and believing in his ability to succeed, Niccol said, has made the biggest difference in his career up to this point. 

"There will be times in your career when your gut will be tingling," he said, noting that he had that feeling when he left Taco Bell to become Chipotle's CEO in 2018. "Make space for that instinctive intelligence and take action. Trust your instincts." 

The confident 5-word phrase Niccol used to get hired as Starbucks' new CEO

While Niccol's experience helped him get his foot in the door for the CEO role at Starbucks, it was his confidence that set him apart from other candidates the coffee chain was considering for the job. 

Niccol used a 5-word phrase in a phone screening with former Starbucks chair Mellody Hobson to illustrate his confidence and preparedness for the job.

"When I talked to him I remember him saying, 'I know what to do,'" Hobson, who ceded her position as chair of the Starbucks board to Niccol and is now lead independent director, said in an Aug. 13 appearance on CNBC's "Squawk Box." 

Hobson continued: "He said, 'This is a speed bump in this company's history. This is not something that I fear going into,' and that was something for our board that was extremely encouraging." 

In his new role, Niccol will be getting paid a base salary of $1.6 million annually and supercommuting from his home in Newport Beach, California to Starbucks' Seattle headquarters on a corporate jet. 

"Brian has proven himself to be one of the most effective leaders in our industry, generating significant financial returns over many years," a Starbucks spokesperson said in a statement to CNBC Make It. "We're confident in his ability to deliver long-term, enduring value for our partners, customers and shareholders."

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