Bill Gates, photographed in 2013 in New York. (Stan Honda/AFP/Getty Images file)

The world's richest man has mellowed over the years. Amassing a net worth of $56 billion while maturing into an altruistic elder statesman will do that to you.

But there was a time, during Bill Gates' early rise to tech superstardom, that the Microsoft co-founder's hyper-competitive personality more closely resembled the ruthless caricature of Steve Jobs than the affable, amiable image associated with Warren Buffet.

Few anecdotes illustrate the relentless force of Gates' early will better than a detail he divulged in a recent radio interview for BBC's "Desert Island Discs" program, which asks famous guests to choose "eight pieces of music, a book, and a luxury item to take with them on a desert island."

In his early years at Microsoft, Gates — once known for pulling all-nighters and crashing on his office floor — was apparently not a big fan of downtime, for himself or anyone else, he told interviewer Kristy Young.

"I worked weekends, I didn't really believe in vacations," Gates said. "I had to be a little careful not to try and apply my standards to how hard [others] worked. I knew everybody's licence plate so I could look out at the parking lot and see, you know, when people come in."

He added: "Eventually I had to loosen up as the company got to a reasonable size."

Gates' unmatched drive and penchant for keeping a close eye on his employees was confirmed in 2011 by Paul Allen in a first-person Vanity Fair article.

Allen, the Microsoft co-founder, described the early days of the company as a "high-stress environment," where Gates "drove others as hard as he drove himself." Allen referred to his former partner as a "taskmaster" who would "prowl" the parking lot on weekends to document who had arrived at work.

Not surprisingly, Gates' monitoring wasn't well-received.

"Bob Greenberg," Allen wrote, "a Harvard classmate of Bill's whom we'd hired, once put in 81 hours in four days, Monday through Thursday, to finish part of the Texas Instruments BASIC. When Bill touched base toward the end of Bob’s marathon, he asked him, 'What are you working on tomorrow?'

"Bob said, 'I was planning to take the day off.'

"And Bill said, 'Why would you want to do that?' He genuinely couldn’t understand it; he never seemed to need to recharge."

At the same time, Allen wrote, Gates respected people who aggressively pushed back, overcoming their boss's skepticism and sometimes allowing both parties to arrive at an unforeseen solution to a complex problem.

As Allen wrote:

Even relatively passive people learned to stand their ground and match their boss decibel for decibel. They’d get right into his face: "What are you saying, Bill? I’ve got to write a compiler for a language we’ve never done before, and it needs a whole new set of run-time routines, and you think I can do it over the weekend? Are you kidding me?"

I saw this happen again and again. If you made a strong case and were fierce about it, and you had the data behind you, Bill would react like a bluffer with a pair of threes. He’d look down and mutter, "O.K., I see what you mean," then try to make up. Bill never wanted to lose talented people. "If this guy leaves," he'd say to me, "we’ll lose all our momentum."

The authors of "Primal Leadership" wrote in the Harvard Business Review some years ago that Gates was one of "those infamous corporate leaders who seem to have achieved sterling business results despite their brutish approaches to leadership."

"Skeptics," they noted, cite Gates "as a leader who gets away with a harsh style that should theoretically damage his company."

But the opposite was true, they wrote: "Gates is the achievement-driven leader par excellence, in an organization that has cherry-picked highly talented and motivated people. His apparently harsh leadership style — baldly challenging employees to surpass their past performance — can be quite effective when employees are competent, motivated and need little direction — all characteristics of Microsoft’s engineers."


Bill Gates at the World Economic Forum in Davos, Switzerland, on Jan. 22. (Michel Euler/AP)

Allen wrote in Vanity Fair that Gates "thrived on conflict" and had no qualms about provoking testy interactions with his underlings.

Sometimes, in the throes of a heated argument, Gates would unleash what Allen called his "classic put-down: 'That's the stupidest f------ thing I’ve ever heard!'"

Gates' penchant for cursing was documented by entrepreneur and blogger Joel Spolsky, the founder of StackExchange and Fog Creek Software. In the early 1990s, Spolsky later recalled on his blog, he began working as a program manager assigned to the Excel product line.

During his first meeting with Gates, the room was filled with multiple layers of management and a person from Spolsky's team who had been designated to keep a tally of Gates' expletives.

"The lower the f--- count, the better," he recalled.

The counter tallied four, Spolsky wrote, "and everyone said, 'wow, that's the lowest I can remember. Bill is getting mellow in his old age.'"

Gates was in his mid-30s at the time, Spolsky noted.

Later, Spolsky learned that the meeting was really just a chance for his boss to test his mettle.

"Bill doesn't really want to review your spec, he just wants to make sure you've got it under control," Spolsky wrote. "His standard M.O. is to ask harder and harder questions until you admit that you don't know, and then he can yell at you for being unprepared.'"

In a Reddit AMA in 2014, Gates was asked what's different about him now.

Plenty, Gates said.

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