How did guilds hinder the development of crafts?

Most of the guilds that were strictly closed to the outside world enjoyed the ancient privilege of refusing to admit outsiders. They admitted only sons who had learned the trade from their fathers, and at most the sons-in-law of old or deceased masters. The number of helpers and apprentices was also strictly limited. In this way, the guild prevented unwanted competition and jealously watched to see that the proprietor of another guild did not take business that did not belong to him. Craft traditions rejected all activities that were not part of the existing guilds. A "servant" outside the privileged guild is considered dishonorable. Only guild owners had the right to trade within the city. This ancient privilege became restricted over time, eventually ossifying the guild system and preventing the creation of new businesses. The young and powerful craftsmen were thus blocked from any possibility of development. The old customs, which had once given prestige and strength to the craftsmen by the strict rules of the guilds, became ossified into empty rituals. Further technological development could no longer be expected from the guilds.