Even the most powerful business people take advice from their best friends.
"The best advice I ever got from Warren was to stop practicing law," says Munger. "He thought it was all right as a hobby, but as a business it was pretty stupid."
The two first met at a dinner party in Omaha, Nebraska in 1959. At the time, Munger was making his mark on the legal profession and co-founded the law firm Munger, Tolles & Olson shortly after.
The business was successful and is still considered one of the most elite law firms, but Buffett envisioned a different career path for his friend.
"It didn't use his full talents," the CEO explains. Buffett says that as Berkshire's chairman he was able to work for himself, rather than for someone else, and he felt Munger would thrive in a similar environment.
"I got to serve myself, to implement my own ideas," he says. "And I knew Charlie was cut the same way."
While Munger had a friend to tell him that he wasn't fully using his talents, many people can see this on their own, says Liz Ryan, CEO of career consulting firm Human Workplace and author of "Reinvention Roadmap."
It's easy to become complacent in a role or career that's no longer fulfilling, she tells CNBC Make It. So it's critical that you analyze whether a job is still helping you grow.
Ryan says there are three signs that can help you see you're not using your full abilities at work:
A lot of people aren't giddy about the start of the workweek. But if Sundays are a downer and you find it difficult to get out of bed Monday morning, these could be physical symptoms that your job is no longer rewarding, says Ryan.
"You shouldn't dread going back to work on Monday," she says. "That's not a good sign. That's not normal."
If trying to get your boss to accept your ideas is a constant struggle, this may signify that you're not fully using your talents.
Ryan says that the main question to ask yourself is, "Am I frustrated with the lack of change and forward motion in my job?"
If you're always pushing against a brick wall, she explains, all that muscle is being wasted.
There should always be people in the office who you look up to and who are willing to help you grow. "If you're the the smartest person in the room, it's the wrong room," says the career expert.
Ryan also recommends reviewing your resume. If you have no new skills to add after a year or more, that's a "really bad sign" that your learning has stalled, she says. "You need to look beyond these office walls."
Changing jobs or professions can be daunting. In fact, Munger tells Fortune, "I kept one foot in the law practice until I knew it was going to work, and then I removed that foot."
Ryan notes that most people don't have that luxury, so she recommends a more releatable approach: While still employed, write down what you dislike about your current role and what you want in a future job, then find positions that align with those needs.
Most importantly, says Ryan, "take your time."
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