Answer:
They stopped foreign thoughts and ideas in their country.
Explanation:
Ming leaders banned further construction of ships because they did not want foreign ideas coming from the exploration of the people and they thought that the people of the country adopt the culture and ideas of the other countries. This decision badly effect the economy of the country because there is no way to export goods to other countries. This decision also causes some good effects on the culture and tradition because there is no other ideas comes from foreign culture into the country.