Howard Schultz took over as CEO of Starbucks when he bought the company in August 1987. At the time, there were six stores.
Today, Starbucks is a global brand. There are more than 25,000 locations across 75 countries, and the coffee company employs more than 300,000 people.
Schultz, who stepped down in April 2017, is largely credited with the company's success. In fact, the news that he was stepping down as CEO briefly sent shares of Starbucks stock down as much as 10 percent.
In an interview with Guy Raz for NPR's podcast "How I Built This," the legendary CEO shared an underrated, yet essential, leadership quality: vulnerability.
"Building a company is a lonely place sometimes because you're imprinted, especially as a man, of not demonstrating vulnerability," says Schultz, who started in the projects before building his $3 billion fortune. "And I think one of the most undervalued characteristics of leadership is vulnerability and asking for help."
It's something he's done "a number of times," he tells Raz. "When you're vulnerable and ask for help, people come towards you. I've tried to do that every step of the way and be honest and truthful about what I know, what I don't and most importantly, what I believe."
Entrepreneur and investor Marcus Lemonis has a similar perspective. Vulnerability is important in business, the self-made millionaire tells CNBC Make It: "So often in business we think that a very proper and stern way of conducting ourselves as know it alls and macho men and women is the way to be. But I actually believe that business is built on relationships.
"Relationships are built on trust, and trust is built on vulnerability and transparency."
On CNBC's "The Profit," in which Lemonis helps turn around struggling businesses, he's often candid in referring to his own business mistakes.
"The key for me in building these relationships with business owners is by starting by unveiling myself first and uncovering my mistakes and my frailties and my weaknesses," says Lemonis. "The only reason that I talk about the rough patches in my life isn't to have people feel sorry for me. It's to try to create relatability between people."
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