Does the customer invent new product or service? The customer generates nothing. No customer asked for electric lights. There was gas and gas mantles, which gave good light.

A system can not understand itself.

Judging people does not help them.

In God we trust; all others bring data.

The most important measures are both unknown and unknowable.

A bad system will beat a good person every time.

The principles and methods for improvement are the same for service as for manufacturing. The actual application differs, of course, from one product to another, and from one type of service to another.