Most leaders, business and political (I'll put religion aside before I get myself into a lot of trouble), lead over very finite times and distances.

Doubtless, determining the limits of those times and distances is very challenging.

My brother frequently tries to impart some wisdom too me. One line that has stuck, arguing effectively against hubris, is that graveyards are full of irreplaceable people.

Thankfully my wife has not yet uttered the same line to me.