Why are there the most traitors and puppet troops in the history of the late Ming Dynasty, and the integrity of the Ming Dynasty is not very good?

It cannot be said that there were the most traitors and puppet troops in the late Ming Dynasty. In fact, there were many in the late Southern Song Dynasty. The former Southern Song Dynasty generals Lu, Liu Zheng, Xia Gui, Fan, civil servant Liu, Wang Jiweng and Ye Li didn't say anything. Even many Yuan generals, such as Shi, Shi and Zhang Hongfan, are actually "Jin traitors". Comparing the late Southern Song Dynasty with the late Ming Dynasty, after Lu surrendered in Xiangyang in the late Southern Song Dynasty, only Zhang Shijie and Wen Tianxiang were the large-scale resistance of court officials, while Li Dingguo, Zhang Mingzhen were all there after Wu Sangui led the Qing soldiers into the customs in the late Ming Dynasty. It can be seen that at least the last years of the Ming Dynasty were not lost to the last years of the Southern Song Dynasty.