The announcement caps a tumultuous six months in which Uber suffered a seemingly endless string of scandals and controversies. They culminated last week with a report by attorney general Eric Holder that found systematic problems with workplace sexism. In the wake of that report, Uber fired one of its top executives, Emil Michaels. And Kalanick himself agreed to take a leave of absence from the company, leaving the company under the control of a committee of Kalanick subordinates.
But hardly anyone was satisfied with that outcome. As I argued on Monday, it left Uber rudderless at a time when it desperately needed decisive leadership. The company has several of its top jobs unfilled, and it would have been difficult to recruit strong candidates without an active CEO.
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Investors evidently felt the same way. According to the New York Times, five of Uber's biggest investors sent Kalanick a letter on Tuesday demanding that he step down as CEO. The investors who signed the letter control about 40 percent of the company's voting power — less than the majority they'd need to oust him, but enough that Kalanick couldn't ignore their concerns.
"I love Uber more than anything in the world and at this difficult moment in my personal life I have accepted the investors request to step aside so that Uber can go back to building rather than be distracted with another fight," Kalanick said in a statement to the Times.
Now Uber needs to find a new, permanent chief executive. As a major Uber shareholder, Kalanick is likely to continue wielding significant influence from the sidelines. But it'll be important that the company's new chief executive be truly independent so that he or she can credibly promise to change Uber's culture and start to put its many scandals behind it.
Uber's new CEO will face big challenges
Since the start of 2017, Uber has faced a number of major controversies:
And there's a real danger that Waymo, Tesla, or another rival could develop fully self-driving technology before Uber, which Kalanick himself has described as an existential threat to the company.
"If we are not tied for first, then the person who is in first, or the entity that's in first, then rolls out a ride-sharing network that is far cheaper or far higher-quality than Uber's, then Uber is no longer a thing," Kalanick told Business Insider last year.
Commentary by Timothy B. Lee, a technology and economics reporter at Vox. Follow him on Twitter @binarybits.
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