Before using facilities? Splain.
K, here is the explanation, in plain, scientific 'Glish.
Imagine a man running around the world, touching and handling all sorts of things in public, and that man suddenly decides he needs to pee. When he gets to the public restroom, he will see one of two versions of a sign. It goes like this...
1. "Employees must wash their hands after using the restroom".
2. "Employees must wash their hands before leaving the restroom".
So, as a man, said man looks at that and thinks, "Hmm, good advice".
He then proceeds to unzip his pants and grasp his penis to direct the flow of the urine into the urinal/toilet, so as to not make a mess.
So the man has grabbed hold of his penis with his hands coated with germs galore BEFORE washing his hands. At that point, he is infected with whatever is on his hands, because the penis has a very very thin epidermal layer, which will absorb many germs (virii/bacterium) those hands may have.
Logically then, the question is begged..."Why would you not wash your hands both
BEFORE and after using the restroom?"