Why did Sun Chang Wuji frame Prince Li Ke?

After Taizong made Li a prince, he rejected Li Zhitai's cowardice and wanted to make Li Ke a prince. Sun Chang has no objection, saying that Li Ke is the grandson of Yang Di. If he is allowed, he will not return to the world of the Sui Dynasty. Li Shimin had no choice. After Li Zhi succeeded to the throne, Sun Chang Wuji came to power. He was afraid that Li Ke and his nephew Li Zhi would seize the throne, so he executed Li Ke on charges of rebellion.