Interesting answer: Because Guan Yu's temper is too bad, at the same time his popularity is too poor.
Unlucky Guan Yu
Let's restore the real situation at that time, that is, after Sun Quan captured Guan Yu, the opinions of all the courtiers of the entire Eastern Wu.
If you hold an annual meeting in a large enterprise, you will find that once the company leader puts forward an opinion, the company's employees will often agree with half and half oppose, and then compromise and then negotiate, right?

But when Sun Quan grabbed Guan Yu and asked the ministers to talk about their opinions,
All the courtiers had only one word, and that was to kill.
This sentence can almost be reduced to one word, and in an absolute sense, guan Yu has no way to live.
The views of the courtiers were also very simple, guan yu had surrendered to Cao Cao in the beginning, but now he had flooded the Seventh Army, forcing Cao Wei to almost move the capital.
It can also be seen that Guan Yu will not be grateful at all, even if he surrenders to us today, he may continue to run to Shu Han on the 2nd day, which is of no use to us.
We can draw such a conclusion,
Almost all the courtiers unified their voices, unified their opinions, and then forced Sun Quan to kill Guan Yu.
Guan Yu's trick
Why did all the courtiers want to kill Guan Yu? In other words, why do these courtiers hate Guan Yu so much? You must know that the distance between Guan YuZhen Shoujingzhou and Eastern Wu is very close, and if the two sides occasionally come to a team-building event or a dinner party in the evening, the relationship will definitely not be so stiff.
The reason is simple, because Guan Yu has never looked up to Eastern Wu, and in his heart he has always felt that Eastern Wu is a group of rats.
This is going to kill people, look down on others, but also fall into the hands of others, in ordinary days for The Eastern Wu finger mulberry scolding to bully others, now that people have the initiative, naturally there is no word: surrender is so simple.
In fact, of this group of Eastern Wu's courtiers and generals and emperors, only one person can take on great responsibilities, and only one person can take care of the overall situation, and this person who takes care of the overall situation is Sun Quan.
Sun Quan originally did not want to kill Guan Yu, but as a result, he was squeezed to the side by the courtiers, and there was no way out, and then he thought about some of the things that Guan Yu had done before, and he was angry from his heart and killed Guan Yu.
The only two people who could save Guan Yu
There are two people in the whole of Eastern Wu who can save Guan Yu, as long as the two of them talk, and Guan Yu comes down the slope of the donkey again, then Guan Yu can definitely live.
The first person who could save Guan Yu was called Lu Su, and Lu Su had a plan at the beginning, and this plan was exactly the same as Zhuge Liang's plan, called Lian Liu Kang Cao and Lian Wu Kang Cao. In other words: Sun Liu united against Cao Wei.
But why didn't Lu Su advise? Because Lu Su was already dead.
Okay, the second person is Zhuge Jin, and Zhuge Jin may also go to save Guan Yu, for the simple reason that Zhuge Jin and Zhuge Liang have a relationship, and Liu Bei was very friendly to Zhuge Jin at the beginning.
So why didn't Zhuge Jin save Guan Yu? There are two reasons, the first reason is that Zhuge Jin needs to avoid suspicion. The second reason and the most important reason is that Guan Yu looked down on Zhuge Jin and provoked Zhuge Jin as well.
Well, Guan Yu seemed to have to wash his neck and wait for the knife on his head.
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