The disengagement rate is calculated when a human test driver is in the vehicle and takes over driving. It's a specific term from autonomous vehicle testing. If

The disengagement rate is calculated when a human test driver is in the vehicle and takes over driving. It's a specific term from autonomous vehicle testing. If a self-driving vehicle has no human drivers in it and it does not know how to drive, it simply pulls over if possible and stops. That's not among the definition of disengagement. This has happened multiple times in San Francisco. You can find videos of driverless Waymo cars getting stuck. You can also find a hilarious instance where a stuck Waymo was driven by the emergency personnel after it became stuck.