Why did Li Shutong become a monk?

Li Shutong became a monk probably when he made great achievements. At this time, his inner relative balance was in a violent turmoil. He needs an abstinence-free Buddhist life and a correct and peaceful Buddhism to restrain the outbreak of demons and resolve the inner imbalance. From another perspective, he was so successful that he had everything he needed, and he finally got tired of worldly ups and downs, which on the other hand prompted him to turn to Buddhist life.