TIL: cutting edge

[timelets]

The principal part of a chisel is the cutting edge. If there is a single principle on which our business rests it is that. It makes no difference how finely made a chisel is or what splendid steel it has in it or how well it is forged—if it has no cutting edge it is not a chisel. It is just a piece of metal. All of which being translated means that it is what a thing does—not what it is supposed to do—that matters. What is the use of putting a tremendous force behind a blunt chisel if a light blow on a sharp chisel will do the work? The chisel is there to cut, not to be hammered. The hammering is only incidental to the job. So if we want to work why not concentrate on the work and do it in the quickest possible fashion? The cutting edge of merchandising is the point where the product touches the consumer. An unsatisfactory product is one that has a dull cutting edge. A lot of waste effort is needed to put it through. The cutting edge of a factory is the man and the machine on the job. If the man is not right the machine cannot be; if the machine is not right the man cannot be. For any one to be required to use more force than is absolutely necessary for the job in hand is waste.

--- Henry Ford, My Life and Work.

It looks like Henry Ford originated this expression.