Dr Deming

is an excellent book by Rafael Aguayo, subtitled The American Who Taught The Japanese About Quality (isbn 0-671-74621-9). This book is also the source of the story about the coffee roasters. As usual I'm going to quote from a few pages
To improve output, production, sales, profit, quality, or any other important factor, every part of the organization had to improve.
Lowering the number of defects in a stable system can only be achieved by working on the system.
A perfectly good system can be ruined by overadjustment and trying too hard.
Overadjustment of a stable system invariably makes things worse. This deserves a special name - tampering.
We are ruined by best efforts. Best efforts without guidance from profound knowledge are oftentimes tampering, ruining perfectly good systems.
The causes of common cause problems cannot be attacked directly.
Good organization is hardly felt and hardly seen. If it is seen and felt, it is most likely the source of problems and therefore the source of loss.
Deming states unequivocally that merit reviews, by whatever name, including management by objectives, are the single most destructive force in American management today.
Running a company by proft alone is like driving a car by looking in the rearview mirror. It tells you where you've been, not where you are going.
The most important thing to know about any tool, including financial reports, is its limitations.
The usual assumption is that each number is due to one cause.
The specification may call for no more than 20 percent defective beads being delivered, which guarantees exactly 20 percent defectives.
Objective observers will only see what they're trained to see.
Because of excessive competition they have been left unable to compete.
If any of us were to purchase everything in our personal lives based on lowest price, we would soon go broke.