Your answer has been basically answered with all the multiple reply's. one more I'll add is that the obvious for emergency, cause the local fire dept. actually requires a certain number of doors on a house for multiple exits. and technically not suppose to be blocked.

people that downvoted are the ones without 4wd. if you have it it does help steer better and brake quicker. it's not a save all but yes its a lot better that your little sedan electric vehicle or your high priced sports car. sometimes going to slow on bad roads is unsafe as well. you gotta go a steady pace so tires are always gripping. hence why 4wd does help

Has anyone actually looked at a sign and been like " oh damn, I like what that says, the sign has convinced me"