“Example is leadership. ”

Recently often attributed to Ordway Tead.
Attributed to Antony Jay in older sources, see: Public Administration Review (1977). Vol. 15. p. 20.
Also called "Jay's Laws of Leadership", see: Paul Dickson (1999) The official rules and explanations. p. 33. This source states:
Jay's Laws of Leadership
#Changing things is central to leadership, and changing them before anyone else is creativeness.
#To build something that endures, it is of great importance to have a long tenure in office-to rule for many years. Quick success can be achieved in a year or two, but nearly all great tycoons have continued their building much longer.
Disputed

Source: In Search of Excellence (1982), p. 82 as cited in: Amir Levy, Uri Merry (1986) Organizational Transformation: Approaches Strategies, and Theories. p. 52.

From 1980s onwards, Only Integrity is Going to Count (1983)
Context: When I was born, humanity was 95 per cent illiterate. Since I've been born, the population has doubled and that total population is now 65 per cent literate. That's a gain of 130-fold of the literacy. When humanity is primarily illiterate, it needs leaders to understand and get the information and deal with it. When we are at the point where the majority of humans them-selves are literate, able to get the information, we're in an entirely new relationship to Universe. We are at the point where the integrity of the individual counts and not what the political leadership or the religious leadership says to do.

"Order reigns in Berlin", Last written words. Collected Works 4 <!-- p. 536 -->
Context: The leadership has failed. Even so, the leadership can and must be recreated from the masses and out of the masses. The masses are the decisive element, they are the rock on which the final victory of the revolution will be built. The masses were on the heights; they have developed this 'defeat' into one of the historical defeats which are the pride and strength of international socialism. And that is why the future victory will bloom from this 'defeat'.
'Order reigns in Berlin!' You stupid henchmen! Your 'order' is built on sand. Tomorrow the revolution will already 'raise itself with a rattle' and announce with fanfare, to your terror: I was, I am, I will be!

As quoted in " 4 Takeaways from Xi Jinping’s Speech Defending Communist Party Control https://www.nytimes.com/2018/12/18/world/asia/xi-china-speech-takeaways.html" The New York Times
2010s

Forward to the book Sai Baba's Mahavakya on Leadership by Lt. General Dr. M.L. Chibber, published by Leela Press, December 1996.
THE AVATAR: IN HIS OWN WORDS

Principles and Priorities : Programme for Government (September 5, 2007)