Bill Gates says Warren Buffett taught him to value free time: Filling ‘every minute of your schedule’ doesn’t make you more serious

As CEO of Microsoft, Bill Gates had a packed schedule — even sending 2:00 a.m. requests to employees.

It wasn't until he saw Berkshire Hathaway CEO Warren Buffett's personal daybook that Gates learned to cut himself and his workers some slack.

"I had every minute packed, and I thought that was the only way you could do things," Gates told journalist Charlie Rose in an interview with Buffett in 2017. "[I] remember Warren showing me his calendar ... he [still] has days that there's nothing on it."

Buffett's sparser schedule taught Gates an important lesson: "You control your time ... It's not a proxy of your seriousness that you fill every minute in your schedule."

"I can buy anything I want, basically, but I can't buy time," Buffett added.

Buffett's method — which is essentially, "work smarter, not harder," — is actually backed by science. Workers' proficiency steeply declines when they work more than 50 hours per week, a 2014 Stanford University study found.

People who work up to 70 hours a week get the same amount of work done as those who hunch over their laptops for 55 hours, the research revealed.

Gates isn't the only CEO to learn that lesson the hard way. For example, Tesla CEO Elon Musk — who previously said he regularly pulled all-nighters to work — now sleeps at least six hours per night, he told CNBC's David Faber in May.

"I've tried [to sleep] less, but ... even though I'm awake more hours, I get less done," Musk said. "And the brain pain level is bad if I get less than six hours [of sleep per night]."

Getting there may not be easy for some people. It took Gates years to find a healthy work-life balance, he said in a recent commencement speech at Northern Arizona University.

"When I was your age, I didn't believe in vacations. I didn't believe in weekends. I didn't believe the people I worked with should, either," Gates said.

"Don't wait as long as I did to learn this lesson," he added. "Take your time to nurture your relationships, to celebrate your successes, and to recover from your losses. Take a break when you need to. Take it easy on the people around you when they need it, too."

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