"Setting an example is not the main means of influencing others, it is the only means," Albert Einstein reputedly said. Exaggeration, of course, but also truth. Other tactics --- threats, arguments, rewards, promises --- may promote good behavior, in a temporary way. But they rarely cause a long-term change of heart. Leaders say "Follow me!", not "Go there."
(correlates: MalaproposDecisionmaking, WriteManyReadOnce, OnGrace, ...)