Fable
Two Report Cards
Old Lin's waterwheel workshop took on a job for a dye house, requiring eight waterwheels to deliver dyes, clean water, cloth rolls, and drying racks to their positions in order every day. The contract had only one clause: the last batch of cloth each day must leave the workshop on time.
In the first month, Old Lin submitted a beautiful set of books: a daily workshop output rate of ninety-seven percent. The dye-works owner was very pleased—until the night-shift workers complained that the waterwheel often jammed midway, was repaired and turned, turned and jammed again, and although delivery was ultimately met, fuel and labor costs had multiplied several times over.
Old Lin crouched by the canal again to watch. Of the eight steps, the first drew water steadily, the second often clogged when adding material, the fourth had to wait for someone to change the cloth roll, and the final drying rack was squeezed into a mess by earlier delays. Looking at the endpoint all day, it seemed everything went smoothly; looking step by step, there were several falls along the way.
He first thought of sending more people to guard the finish line and urge them on. The urging grew louder, but the blockage did not disappear. Someone else said to simply rerun from the beginning after every failure. The cloth could come out, but at night a long queue formed.
Old Lin kept separate accounts for each waterwheel: which one stopped, for how long, why it stopped, and whether it could be repaired locally. The feed inlet was changed to dual slots, cloth roll changes were prepared with advance tags, and drying racks were separated by batch to wait, no longer forcing the entire line to rerun from the start.
Three months later, the final output rate was still 97%, but the proportion of waterwheels passing smoothly was much higher, and the night shift finished two hours early. Only then did the owner understand: arriving at the same destination by running smoothly the whole way and by falling and scrambling up the whole way are completely different in cost.
From then on, Old Lin required two lines side by side in the ledger: the first line to see whether the whole job was completed, the second to see whether each step went smoothly. The larger the gap between the two lines, the more the endpoint number hides problems on the ground. Later, when he took on new work, he first asked the client which segment they were willing to pay to make more stable. Looking only at final delivery, the workshop would conceal rework; seeing each step clearly, you know whether to fix the waterwheel, add hands, or change the whole waterway. He also found that some clients care only about the endpoint, while others care more about process stability. The former will tolerate rework; the latter cannot accept midnight fixes. Once the two ledgers were separated, the workshop knew whether it was selling on-time delivery or predictable operation.