A relative of mine rear ended someone and couldn't understand why they were at fault for the accident. Just kept saying the person in front of them just stopped out of nowhere and there was nothing they could do.

People just don't realize they're supposed to give that much distance to the person in front of them. You're supposed to be able to stop without hitting the person in front of you if they, for any reason, stop without warning.

In my area the driving manual only discusses stopping/following distances for the commercial drivers license, not the standard drivers license