In Eliyahu Goldratt's novel The Goal, a scoutmaster takes a troop of boys on a hike. They walk in a line that stretches longer as the hike progresses.
The fast boys stride ahead, gaps open, and the whole troop arrives no faster than one slow boy in the middle, Herbie, carrying a pack stuffed with treats.
The scoutmaster does something odd.
He puts Herbie at the front, where the whole line has to walk at his pace, and then he empties Herbie's pack into the other boys' bags.
Herbie, lighter without the contents of his pack, speeds up.
Nothing else was changed.
That one change caused the whole troop to speed up.
Goldratt built the Theory of Constraints on that hike. Every system has its Herbie, one constraint that sets the pace of everything, and effort spent anywhere else is decoration. Most organisations, meanwhile, are busy training the fast boys to walk faster.
See also: Theory of Constraints — from the Whole Earth catalog