Fable
The postman and the route the postman walks every day
Old Lü, the town postman, set out with his mailbag at six every morning. He first checked the weather, then decided his route based on how thick the day's mailbag was; South Street, East Lane, the mill to the north, the market to the west—he remembered which door had a dog and which alley was shaded in the morning.
A young administrator newly arrived at the post office looked at the delivery records and was dissatisfied. He changed the map on the wall and required Old Lü to go north first the next day. Old Lü complied, and came back with four fewer letters; the street sign at the north dock alley had fallen, so he took one extra turn and missed half an alley.
The administrator asked in confusion, you know the route, so why would changing the route cause missed deliveries? Old Lü said, when the route changes, where you stop, where you turn, and which household requires someone to sign for receipt all change. The person is still the same person, but the rhythm of what he does every day has already changed.
The two of them argued all the way up to the bureau chief. The chief did not first judge who was right; he only asked Old Lü to draw the route he had actually walked the day before. That line twisted and turned, avoiding the alley entrance where the road was being repaired, and also bypassing the busiest market entrance on Wednesday market day.
The bureau chief then had the administrator draw the new route he had envisioned. The new line was very straight and looked beautiful, but it did not mark the fallen street signs, the temporarily closed bridge, or the elderly people who needed to sign in person. The route on paper is about arrangement; the route underfoot is about execution.
From then on, the post office kept two things separate: Old Lü himself had an identity, a mailbag, keys and responsibilities; how he observed, judged, delivered and adjusted step by step each day on his rounds was another matter. Swapping the person and swapping the method fix different problems.
The administrator later wrote this lesson in the record book: when the postman makes a mistake, don't rush to replace the postman, and don't just change the map on the wall. Look at whether the person is matched, and also at whether his round-by-round way of working catches the changes on the ground.
Later, an even thornier job came along. On the surface it looked like just an amplified version of the old problem, but in fact it forced out all the gaps hidden in the process: who takes over first, who can make changes, how to return to the previous step when something goes wrong—places that used to get by on the tacit understanding of acquaintances now all had to be spelled out clearly. The person in charge did not urge everyone to be more careful again; instead, he walked through the site once more. He had people record every handover, every failure and every remedy, which places were merely slow, which places would harm the results, and which places would be hard to trace back once a mistake was made.