Such a weak joke. It doesn’t even make sense. There are more than two ‘ways’ that a sign can go, so the word “both” doesn’t fit. Also, why are the signs black? If you wanted that joke to make sense, you should have had a mom and dad escalator (one up, one down) and then the son is an elevator. (up and down). Please Dave… either put some more effort into your work or just stop all together.