Classicly

A Message to Garcia is a widely distributed essay written by Elbert Hubbard in 1899, expressing the value of individual initiative and conscientiousness in work.

Excerpts from the book:

If you work for a man, in Heaven's name work for him. If he pays wages that supply you your bread and butter, work for him, speak well of him, think well of him, and stand by him, and stand by the institution he represents. I think if I worked for a man, I would work for him. I would not work for him a part of his time, but all of his time. I would give an undivided service or none.

If put to the pinch, an ounce of loyalty is worth a pound of cleverness. If you must vilify, condemn, and eternally disparage, why, resign your position, and when you are outside, damn to your heart's content. But, I pray you, so long as you are a part of an institution, do not condemn it. Not that you will injure the institution—not that—but when you disparage the concern of which you are a part, you disparage yourself. And don't forget—“I forgot” won't do in business.