← all lessonsLESSON 2 OF 8 · ASHBY’S LAW OF REQUISITE VARIETY; THE JOIN FORM
Who is in the room
The map can only contain causes someone in the room knows. A room of twelve planners will find planning causes. The method calls this requisite variety: the variety of the people must match the variety of the problem.
Your roster for “What is driving delivery delays?” is fourteen people from dispatch and planning. What do you do?
✗ Not that one. The method’s answer is marked below; read why yours is not it.
Run it — fourteen is enough and they know the operation best.✗ not this · your pick
They know their half of it. Drivers, the yard, a customer and a customs clerk hold causes nobody in dispatch has seen.
Invite four more from other parts of the chain, even if the room becomes twenty.✓ what the method does
Variety beats size. Eighteen with drivers, yard and a customer in it will find causes fourteen planners cannot. Twenty is still one group.
Split them into two groups of seven so more voices are heard.✗ not this
Below twelve a panel starts losing causes, and the two groups would still be all planners.
ON THIS PLATFORM
The join form asks each person where they stand, in a word — night shift, management, customer — and when the room is cut into groups those perspectives are dealt across them so no group is all one kind.