The three most unsustainable generals in history, after their death, the country immediately perished.
The first Wu Zixu

Wu Zixu helped Lu to seize the throne of Wu, and developed the military strength of the state of Wu, which was reused. After defeating the Yue king Gou Jian, Wu Wang Fu Cha listened to Dazai Yao's plan and spared his sworn enemy Gou Jian, thus giving Gou Jian the opportunity to revive.
And Wu Zixu, who has penetrated the hearts of the people, has repeatedly tried to persuade fu to send a messenger and kill Gou Jian to avoid any trouble. Fu Cha not only did not listen, but alienated Wu Zixu. Later, under the slander of Dazai, Fu Cha gave death to Wu Zixu. After Wu Zixu's death, the State of Yue took advantage of the fact that the State of Wu sent troops north to secretly attack the State of Wu. In the end, after destroying the State of Wu, Fu Cha regretted not listening to Wu Zixu's words before he died, and covered his eyes with a black cloth to show that he saw Wu Zixu underground without a face.
The second Yuan Chonghuan
Yuan Chonghuan led the Ming army to achieve the Great Victory of Ningyuan and the Great Victory of Ningjin, and severely damaged Houjin. Yuan Chonghuan insisted on staying in Liaodong, which undoubtedly became the hardest northern barrier of the Ming Empire.
In the second year of Chongzhen, the Emperor Taiji, who had no way to take Yuan Chonghuan, detoured through Mongolia and avoided Yuan Chonghuan's defense zone. Invading the Ming Dynasty from Da'ankou, and before Emperor Taiji attacked Da'ankou, Yuan Chonghuan repeatedly went to the imperial court and proposed to strengthen the weak defense of the Jimen land in case of a sneak attack by Houjin. However, due to various reasons, it was not adopted, and as a result, Houjin did sneak up on this place and fought all the way to the city of Beijing, and the Ming Dynasty was once again in danger. At a critical moment, Yuan Chonghuan led his generals to fight to the death, only to be able to repel the Emperor Taiji and save the capital.
Afterwards, Yuan Chonghuan was accused of conspiring against the emperor and executed. The Ming Empire also collapsed within a decade of his death. Some people say that the biggest unjust, false and wrongly decided case in Chinese history was not Song Gaozong's killing of Yue Fei, but Chongzhen's killing of Yuan Chonghuan. However, some people believe that Yuan Chonghuan killed Mao Wenlong privately and deserved to be blamed for Ling Chi.
The third is the one who is blessed
Meng Tian was a famous general of the Qin Dynasty and was deeply respected by Qin Shi Huang. At that time, he and his brother Meng Yi were known as "faithful".
After the unification of Qin, Meng Tian led a 300,000-strong army to attack the Xiongnu in the north, recover Henan, and led the army to repair the Great Wall and the Kyushu Straight Road.
In 210 BC, Qin Shi Huang fell ill and died on his way out. Zhao Gao and Li Si jointly created a fake edict and ordered Fu Su and Meng Tian to commit suicide, and Fu Su committed suicide without distinguishing between true and false. Meng Tian did not want to commit suicide and asked to appeal to Hu Hai. Zhao Gao's emissaries imprisoned him, and after Meng Tian was imprisoned, he again asked the state to give him the opportunity to appeal. However, the Qin Dynasty under Zhao Gao's dictatorship was full of darkness, and there was no way to appeal, so Meng Tian had to commit suicide by taking poison with hatred. Since then, the State of Qin has no longer been able to turn the tide of the tide.
Three years later, the Prince of Qin surrendered to Liu Bang, and Qin II died.