“when we examine managerial productivity, we’ll see that when a manager digs deeply into a specific activity under his jurisdiction, he’s applying the principle of variable inspection. If the manager examined everything his various subordinates did, he would be meddling, which for the most part would be a waste of his time. Even worse, his subordinates would become accustomed to not being responsible for their own work, knowing full well that their supervisor will check everything out closely. The principle of variable inspection applied to managerial work nicely skirts both problems, and, as we shall see, gives us an important tool for improving managerial productivity.”