A military idea, embodied in Sun Tzu's 9 principles of war as "unity of command". There should be one, and only one, final authority on every decision, and all decisions should be made at the lowest level possible.
A chain of command has one commander in chief, who is in charge of a number of staff officers. Each staff officer is in charge of a number of subordinates, and so on down to the man who shoots the enemy. When the General says, "hold the fort," his staff come up with a plan to hold the fort, and pass out parcels of that plan (hold the north wall, hold the gates, etc.) to their men. The riflemen are commanded in small groups by a sergeant who gives them a specific order like "shoot anyone who gets near this wall."
Complaints and status reports flow up the chain, orders and blame flow down the chain. Both need to be handled at the lowest level possible. "Use the chain" is often heard as the vanilla solution to any military problem, but if your shoe is untied, don't ask the sergeant what to do; he's got 5 other men to worry about. This idea can be applied to problems in real life as well. Suppose you find a broken node. First, /msg the author of the node and tell them that you suspect brokenness. If they can't or won't fix it, then post it to Broken Nodes if you think it's really important. Even if this doesn't work, do not /msg pingouin every time you see a typo.
In any military organization, your chain of command will often be drawn on an org-chart, which ends up looking like Zeus' family tree or a bowl of pasta.
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