Waymo is a technology provider. Uber has lots of existing users and no ability to do autonomous driving. This way, Waymo gets to enter their cars in Uber's app and make a similar kind of revenue as a driver would. All Uber does is take their cut and supply passengers.

So Waymo doesn't have to duplicate all of what Uber already does, Uber users just order their ride as normally and maybe get a little cost benefit out of there not being a driver or a need to tip them, and Waymo gets to focus on the cars and the driving and rolling out in more cities.

I don't see how Waze or Google factor into this. Not really a competitor to Uber or taxis in general.