I once witnessed an egregious example of not understanding the rules:
A traffic light changed and a car stopped in the intersection to wait
for it to turn green again.
Though we call it a stop light, a red light doesn't mean "stop". It
means "it is not your turn to use the intersection". Had the driver
understood this, he wouldn't have remained in the intersection when it
wasn't his turn.
The most-common way to avoid entering an intersection is to stop, but
it's also permitted to move slowly enough that the light turns green
just as you reach it, or to turn off on a side road if one presents
Likewise, a green light isn't a command to shut your eyes and plow
straight ahead. A green light grants permission to enter the
intersection if it is, in your considered opinion, safe to enter the
joy beeson at comcast dot net
The above message is a Usenet post.
I don't recall having given anyone permission to use it on a Web site.