What directly led to the variety and sudden increase of military books in Ming and Qing Dynasties?

The Ming and Qing dynasties were in the late feudal society, and the ancient art of war thought was constantly summarized and innovated during this period, and the compilation of Sun Tzu's Art of War reached the most prosperous stage. Frequent large-scale wars in Ming and Qing Dynasties accumulated rich experience for the innovation of art of war. In the wars of this period, there was a war of changing dynasties. Frequent wars provide new materials for the progress of military science, especially the improvement of weapons and the changes of arms, and put forward new requirements for the development of the art of war. The weapons and equipment in Ming and Qing dynasties were more sophisticated than those in the previous generation. Firearms have been improved, their lethality has been greatly improved, and their types have increased day by day, gradually occupying an important position in the battlefield. The renewal of weapons has brought about many changes in the military establishment, logistics supply, strategy and tactics and operational command, and new arms such as artillery, muskets and engineers have also appeared in the military. In this case, in order to adapt to the new war, the art of war thought of Ming and Qing dynasties was innovated on the basis of summarizing the achievements of predecessors, and a number of military books such as firearms, gunpowder, new tactics and new army system came into being. According to relevant bibliographic records, there were more than 2,000 kinds of art books produced in Ming and Qing Dynasties, and there are still 1059 kinds. These military books reflect the popularization and improvement of military thoughts and knowledge in Ming and Qing Dynasties.