...the road sign says.
Suggesting, presumably, that you should be careful, should try to get home safe.
(Though you could just as easily read it as a exhortation to hurry: someone is waiting for you at home.)
But what if it's not true? What if you're driving alone, late at night, back to an empty house? So that the sign is a taunt pushing you over the edge? So that you shut your eyes, spin the wheel wildly? The outraged cacophony of horns, the explosion of pain. Then darkness.
(This is why I don't drive)