Hygienic Employees
More often than not, if a sign doesn’t have the correct punctuation, it can very easily be misconstrued. And when it comes to workplace activity or customer service, you want to limit confusion as much as possible. There are plenty of customers breathing down your neck already, you don’t need anymore.
To be honest, the use of a little bit of grammar could have helped this situation, but the sign isn’t actually unclear. This customer either has this kind of experience in other public bathrooms or just really can’t piece together a sentence without the correct grammar.