In order to achieve the highest degree of specialization and the lowest cost with the largest batch of assembly line production, Henry Ford is not allowed to have any spare parts and devices in automobile design. In order to reduce the production time lost by changing the mold, and to avoid the equipment cost and inventory cost inevitably brought by a wide variety, Ford only produces a single model and a single color T-car. Its salespeople have repeatedly proposed to increase the paint color of cars. Ford's answer is: "any color the customer wants, as long as it is black." It seems that the original words in an article are like this. In order to improve production efficiency and achieve mass production at a lower cost, Ford doesn't seem to care about the color of the car, because it will raise the cost, so as long as the price of the car is low enough, people will buy it regardless of the color. This is my understanding.