My hypothesis is that in the early days the key to success for robotaxi service companies is going to be safety and consistency, in order to convince regulators that huge fleets of robotaxis are safe. "Early days" doesn't just mean the current technical workup period -- it also covers the time period where robotaxi services start to eat into the market for privately-owned cars. That's the point where you'll see the heaviest anti-robotaxi lobbying from entrenched competitors, which will include not just taxi services but also politically-connected interests like car dealerships, manufacturers, service centers, etc. These folks will see their entire livelihood disappearing, and "robotaxis aren't safe" is the obvious argument they'll turn to.

During this period, it seems like a huge risk for a robotaxi company to play it "fast and loose" with car quality or maintenance. You'd want to maintain exceptional standards on anything safety-critical, and that means you don't want to be seen as outsourcing critical hardware purchases and maintenance to random sole-proprietor businesses. (Maybe somewhere down the line this will change, when the tech is so advanced and accepted that anyone can offer it.)

Obviously I might be wrong. Maybe capital is going to become so tight that it'll be hard for the Waymos of the world to scale up quickly? But at least for the first, say, 7 years of major expansion it feels like safety and quality are going to dominate the conversation.