I would actually put money that this is the cause of most crashes involving multiple moving cars. Hell, a friend of mine got into an accident two weeks ago where they t-boned somebody that turned onto a median when they didn't expect it.

This is literally the cause of almost every human accident.

Imagine you're driving. There's a car in front of you, also driving, at the same speed as you. Do you immediately slam on the brakes? No, because you EXPECT them to keep driving. That is how driving works.

If, suddenly, they do something unexpected - like slam on the brakes, that might cause an accident. Because ... they moved in an unexpected way.

I honestly can't even figure out what you meant to say.

Well obviously even Waymo agrees, given that they're recalling vehicles to mitigate the issue.