The high prices limited the market to persons of means. However, princes and nobles at first scorned the books produced in quantities and continued to purchase only manuscript copies. The clergy and the lawyers were less reluctant to accept substitute for manuscripts.
But the rapidity with which books came off the presses soon caused a glut on the market, because the reading public was not yet used to the idea that it could afford to buy more books. After eight years of hard, steady work, Sweynheym and Pannartz were caught in the first depression of the book trade with no cash and with all their funds tied up in a large stock of unbound copies. They implored Pope Sixtus IV to aid them, listing their inventory of 12,475 books. They complained that this accumulation crowded their quarters, so that they could scarcely move and even had to beg for their daily bread.
Florence Edler de Roover, New Facets on the Financing and Marketing of Early Printed Books. Bulletin of the Business Historical Society, Vol. 27, No. 4 (Dec., 1953), pp. 222-230. http://www.jstor.org/stable/3110897
Also see http://dx.doi.org/10.1080/13688804.
In the 1960s, there was a similar event in Silicon Valley during the microwave boom and bust cycle when the military suddenly reduced its purchases of radar-related equipment.
In the 1920s, the first bread slicing machines had a similar problem.