No, I'm implying that people who maintain their own cars do it more efficiently. The simple stuff like cleaning has to be done by someone. It's not about doing a "worse job," it's about doing a more expensive job.
Waymo is replacing human drivers with a capital-intensive fleet business, a substantially more expensive vehicle, and still a large number of remote assistance staff, fleet operators, safety engineers, incident response, operations staff, etc.
But I'm not saying they can't beat a human driver, I'm just saying it hasn't been proven that they will. It may only be that the highest demand markets will provide a sufficient enough utilization to make it economically viable.