Uber took 14 years to make it to profitability. Money's frequently characterized as impatient, unable to look past the next quarter, but when it wants to be, it can wait.

Waymo's older than Uber, but they hold many key patents by this point. Now that they've started running a taxi service, it seems straightforwards to scale up, assuming that is the business they want to be in. Then it's just a matter of charging more than it costs to run the service, and wait.