How to use the facilities?!

Everyday I see this sign on the back of the toilet doors in the library and it tickles me every, single time! Why oh why do we need instructions guiding us how to use a toilet?!

As Einstein once said...""It is nothing short of a miracle that modern methods of instruction have not yet entirely strangled the holy curiosity of inquiry."

(picture taken on my phone, it seems too strange...taking my camera out in a toilet!!)