To do the most good requires saying no to pressures to stray, and the discipline to stop doing what does not fit. - Peter Drucker

People in general, and knowledge workers in particular, grow according to the demands they make on themselves. They grow according to what they consider to be achievement and attainment. If they demand little of themselves, they will remain stunted. If they demand a good deal of themselves, they will grow to giant stature — without any more effort than is expended by the nonachievers.

Few companies that installed computers to reduce the employment of clerks have realized their expectations; most computer users have found that they now need more, and more expensive clerks, even though they call them "operators" or "programmers.

But innovation and change make inordinate time demands on the executive. All one can think and do in a short time is to think what one already knows and to do as one has always done.