Fable
The backyard mechanism and the little cart that goes to market
There was a carpenter in town who spent half a year building an automatic cargo mechanism in his backyard. Gears meshed, levers linked, and the cargo bucket could run back and forth between the two ends of the yard. When neighbors came to see it, they all found it amazing and said one after another that it would surely sell. The carpenter was greatly encouraged and spent another two months making the mechanism smoother and more beautiful.
Another carpenter looked for three days and then walked away. Three months later he pushed a crude four-wheeled cart onto the street. The cart was not pretty, the boards were nailed crookedly, it could only move on flat ground, and it had none of the refinement of a mechanism. But he helped people haul goods at the market entrance, earned twenty wen in one morning, and received six pieces of feedback: the wheels were too small and got stuck on stones, the handle was too high and tired the shoulders, and the cargo bed had no sunshade so goods easily got damaged by the sun.
More and more neighbors came to see the first carpenter's mechanism. Some said they would write him a recommendation letter; some said they could introduce investors. But no one actually paid to buy it. The mechanism could only demonstrate one shipping route; if the cargo changed size, it could not move, and if the road was uneven, the gears jammed. The carpenter wanted to improve it but did not know where to start, because it had never run for a single day in a real market.
The second carpenter used the money he earned in the first week to buy four large wheels, added a sunshade in the second week, and adjusted the handle height in the third week. His cart still wasn't pretty, but after every change someone was willing to try it again, and after every trial someone continued to pay. Half a year later, the onlookers in the courtyard had dispersed, and the delivery cart on the street had a stable customer base and weekly income.
The first carpenter finally tore down the backyard wall and wanted to bring his contraption onto the street. But bringing it out wasn't enough: it lacked brakes, a seat, loading and unloading procedures, and a way to repair it if it broke on the road. Neighbors were willing to lift it for him and help watch it, but couldn't guarantee someone would still be willing to pay tomorrow.
The town chamber of commerce later wrote a rule: any project applying for a storefront loan must clearly state how many copper coins it has already collected, and cannot rely only on how many cheering neighbors have passed by. The backyard proves the feasibility of the idea; the street proves the feasibility of the business. The two kinds of proof point to different next investments.
The carpenter later learned this too: first use scrap wood in the backyard to test whether the mechanism turns, then nail together a cart that can go out on the street to see if anyone will pay. Whether the mechanism is beautiful does not matter, and whether the cart is crude does not matter. What matters is not doing the two things on the same day and not confusing the questions each is meant to answer.