Why did the total industrial production in Spain decrease by the 13th century compared to the 10th century?

The conquest of the lands of the weakening Emirate of Cordoba by northern Christian feudal lords led to the decline of urban culture and many crafts.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.