Not a joke, but amusing.
There is a well know chain store in America that has a policy of hiring retirees.
At one particular store they hired an elderly man that never came to work on time, however, after he arrived he performed all of his work extremely well and was very polite and well disciplined, one day the store manager called him into his office to talk with him,
"You know sir, I find your work ethics exceptional and your personality is impeccable, however there is just one problem, your tardiness,"
"Yes, the worker replied, I'm aware of the problem and I will try to be on time,"
"I'm curious, said the manger, what happened during your career, before you retired, when you came to work late?"
"They usually snapped to attention and my aide would ask me, 'would you like your coffee now, Admiral?' "