Why can't movable type printing in Bi Sheng completely replace block printing in ancient China?

First, during the Yuan, Ming and Qing Dynasties, a large number of Buddhist scriptures, novels and scripts were printed into books. This kind of book is characterized by many illustrations, and is called Xiu Xiang Edition. Illustrations cannot be printed with movable type, so they can't be replaced for a while. It was not until hundreds of years later, after the invention of photography, that the engraving printing industry gradually withdrew from the historical stage.

Second, movable type printing has just begun, and typesetting must be operated by people who understand Chinese characters if it wants to work effectively. At that time, education was not popular, and ordinary craftsmen from poor backgrounds could not do this. What they can do is usually more than several times that of poor craftsmen, which leads to the increase of movable type printing cost. Moreover, for the old craftsmen whose skills are improving day by day, the error rate of lettering is quite low, and the situation of engraving a board is not as much as that of later generations, so the cost is still more cost-effective than movable type.

Third, the quality of movable type printing is not guaranteed. At first, movable type printing was made of wood, which was difficult to process. It is difficult to keep the symmetry of strokes and the same height of movable type blocks in a small square inch, which leads to different ink colors of printed books. This kind of quality, compared with the engraving on the flat plate, can't be compared at all However, the quality of clay printing is limited, but the cost of firing movable type blocks will increase, so it is not used.

These are the reasons recognized by researchers now.