Mr Gates shifted his focus away from the computer giant many years ago, preferring to devote his time and public profile to improving world health though the Bill and Melinda Gates Foundation, the charity he established with his wife.
The stepping down comes at a crucial juncture for the company. Mr Gates built the computer giant on the principle that if the software was good enough, the rest would surely follow. It was a strategy that worked for decades. Microsoft Windows was so far ahead of the competition, computer manufacturers installed it in their products by default.
However, the world eventually changed around it and gadgets rather than software became the keys to success. Apple set out with the opposite vision, staking its future on the notion that if its hardware – glossy Macs, iPhones and iPads – was good enough, it could persuade customers to swap Windows for their own iOS platform. The company that had once nipped at Microsoft’s heels toppled it from its position as the biggest technology business in the world.
Somewhat reluctantly, Microsoft was forced to change. Over the past two years, it has produced its Surface tablet, bought Nokia’s mobile handset business and launched Windows 8, a radical reinvention of its iconic operating system that is designed to allow people to flip easily between tablets and PCs.
None of these initiatives caught the public imagination, and the launch of Windows 8 ranked as a disaster, both in its timing and execution. Morale suffered, with staff and investors complaining that the computer giant had lost its culture of innovation.
The cycle of decline has also taken its toll on Microsoft’s shares.
Just nine years before Gates quit as Microsoft CEO, he was riding high and Jobs was the man running two failing companies: NeXT and Pixar.
When Gates stepped down as CEO, he said he would stay on as “chief software architect.” He gave up day-to-day responsibilities at Microsoft in June 2008 to work on his charitable ventures.
One possible reason behind his decision to leave his job as CEO: Microsoft faced increased antitrust scrutiny, which undoubtedly made the job less fun than before.
The 52-year-old, whose boyish looks seem at odds with his graying hair, will leave behind a life’s work developing software to devote energy to finding new vaccines or to micro-finance projects in the developing world.