"A manager is responsible for the application and performance of knowledge." — Peter Drucker

The most efficient way to produce anything is to bring together under one management as many as possible of the activities needed to turn out the product.

Business, that's easily defined - it's other people's money.

Checking the results of a decision against its expectations shows executives what their strengths are, where they need to improve, and where they lack knowledge or information.

If analysis shows that someone's brilliant work fails again and again as soon as cooperation from others is required, it probably indicates a lack of courtesy - that is, a lack of manners.