Here you can find the best quotes from Peter Ferdinand Drucker grouped by book. managing oneself quotes Visit Amazon for details and reviews about this book. image/svg+xml There is nothing so useless as doing efficiently that which should not be done at all. Success in the knowledge economy comes to those who know themselves - their strengths, their values, and how they best perform. Like so many brilliant people, he believes that ideas move mountains. But bulldozers move mountains; ideas show where the bulldozers should go to work.