From day one, Uber and all of its investors understand that they need self-driving cars to be profitable. Human drivers represent the single largest expense in non-autonomous ride-sharing at 80% of the total per mile cost. By removing the driver from the equation, fully autonomous vehicles dramatically lower the cost of a ride while boosting its addressable market.
That's why Uber invest so much money into their self-driving car unit. Uber’s self-driving unit, the Advanced Technologies Group (ATG), has an estimated valuation of over $7.5 billion, representing over 14% of Uber’s current market cap of about $51.7 billion. Uber's goal from the very beginning is to eventually remove all of its human drivers.