The social system was very fixed and unchanging during the Middle Ages. The system of laws of the Middle Ages was built on the fact that society did not change. Everyone had their place in the system and they stayed there. The lords who built the bastide did not want to change the social system. All they wanted was small local improvements. Usually, the land where the bastide was built was not developed. The lords that owned the land were not making much money from it. They built the bastide because they hoped they would get more profits from the land.