[ra7]

They don't avoid left turns. There are plenty of videos from Chandler, AZ of Waymo performing unprotected left turns perfectly fine.

They will always map roads to precision, whether it's Arizona or San Francisco. Why is that a problem? You should either look at their CA disengagement reports over the years or wait until they roll out a service in SF (where they've been testing heavily). That will show how safe they are in dense environments.

[olau]

From what I gather, they manually mark sections as hard when the cars get stuck there, e.g. due to road work, and then their routing system chooses another route, e.g. one that avoids the left turn.

The video with the Waymo car getting stuck and taking off from the rescue team had an example of this.

I guess it makes perfect sense from a engineering perspective.