I am so confused by Uber's financials. I do not understand what they spend well over 8.5 billion on. Their software for riders and drivers is quite good and c

I am so confused by Uber's financials. I do not understand what they spend well over 8.5 billion on. Their software for riders and drivers is quite good and certainly tons of engineer-hours have been poured into the front and back ends. Are they paying their drivers more than they're charging riders? Or have all the billions gone into their moonshot projects like self-driving cars? Both? Because otherwise, to me it's almost like, how do you not turn a profit on rides? Once they've got their app and infrastructure going (again, no small expense) then any rides they arrange should be profit. Clearly, I am misunderstanding something about their business to an astronomical degree but I don't think I'm alone.