Do you know what makes a leader? It’s the man or woman who can persuade people to do what they ought to do — and which they sometimes don’t do — without being persuaded. They must also have the ability to persuade people to do what they do not want to do and like it.

Harry S Truman (1884-1972) US President (1945-1953)

Speech, Annapolis (24 May 1952)
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Truman used this phrase multiple times in his speech and writing:

• Common paraphrase: "You know what makes leadership? It is the ability to get men to do what they don't want to do and like it."
• "I could see that history had some extremely valuable lessons to teach. I learned from it that a leader is a man who has the ability to get other people to do what they don't want to do, and like it." -- Memoirs, Book 1 (1955)]
• "My definition of a leader in a free country is a man who can persuade people to do what they don't want to do, or do what they're too lazy to do, and like it." -- Where the Buck Stops (1990) [ed. M. Truman]