What makes investors push out a C.E.O.? Scandal, yes. But also plain old fear for their money.

Another good summary by The New Yorker of the reasons why the board ousted CEO Travis Kalanick:

There are many examples of corporate behavior that violates rules but bolsters profits […] but what set Uber apart was the way the company was celebrated for its better-to-ask-forgiveness approach to business.

Still, for all Uber’s success, there was a more urgent problem that caught investors’ attention. […] Uber was losing enormous amounts of money. “The burn rate was alarming,”

Uber’s board members were rattled by the Delete Uber campaign, during which around half a million consumers were believed to have wiped the Uber app from their phones.

https://www.newyorker.com/magazine/2017/07/10/ubers-opportunistic-ouster