Zhuge Liang is an image of a "multi-wise and almost demon" in the "Romance of the Three Kingdoms", who can borrow arrows from the East Wind and can observe the heavens and people. In fact, we know that the author put the Shu Han clique in an orthodox position, and Zhuge Liang just adapted to the role of "loyal subject", so it is normal to be glorified. The real Zhuge Liang is not a perfect person, he also has times when he looks away.
When Zhuge Liang was in Liu Beisan's gu maolu, he once took out the "Longzhong Pair" to analyze the general situation of the world to the head, which was Zhuge Liang's highest achievement in looking at the world; and Zhuge Liang's two times in his life looked at the wrong person, and both of them profoundly affected the fate of Shu Han and also created two major points of controversy in Zhuge Liang.
The people who were overestimated by Zhuge Liang's ability knew that it was Ma Chen. However, Zhuge Liang's attitude toward Ma Mo has always had some doubts, first of all, in 223 AD, before Liu Bei died of illness in the White Emperor City, he had specifically instructed Zhuge Liang that Ma Mo was "exaggerated, exaggerated, and not useful", why did Zhuge Liang not listen?
The author believes that Zhuge Liang once compared himself to Guan Zhong and Le Yi when he was in Longzhong, and after following Liu Bei, Zhuge Liang also put himself in a position of giving advice and taking charge of the overall situation, and people in this position must have extreme self-confidence, but Cheng Ye Xiao He defeated Xiao He, and Zhuge Liang's self-confidence in understanding people was placed on Ma Mo, which made him suffer a big loss.
Secondly, before Zhuge Liang led an army to fight against Yongmin, Ma Mo did give good advice on "psychological warfare first" and helped Zhuge Liang pacify the south, but Ma Mo did not personally lead his troops to the battlefield except for making suggestions; in 228 AD, Zhuge Liang went out of the Qishan Northern Expedition, and the strategic place of Mian Jie Street Pavilion was a strategic place, why did Zhuge Liang go against the opinions of everyone and insist on letting Ma Mo lead the troops as the vanguard?
The biggest possibility is that Zhuge Liang is giving Ma Mo a chance to make a contribution. In Zhuge Liang's position, it is not enough to have loyalty and ability, Zhuge Liang also needs to cultivate a certain amount of power. In the Romance of the Three Kingdoms, it was Ma Mo who took the initiative to ask Zhuge Liang to send him; and in history, Zhuge Liang sent Ma Mo after his own consideration, which led to the defeat of the street pavilion and the failure of the Northern Expedition.
The person whose loyalty was underestimated by Zhuge Liang was the famous general Wei Yan. Although Wei Yan did not rank among the "Five Tiger Generals", his strength could not be questioned. Coincidentally, Wei Yan's situation was the complete opposite of Ma Chen's, because Liu Bei appreciated the reuse of Wei Yan during his lifetime, and by the time of Zhuge Liang, Wei Yan's status had become somewhat delicate.
In 219, Liu Bei was proclaimed the queen of Hanzhong, and everyone thought that he would let Zhang Fei be the Taishou of Hanzhong, but Liu Bei unexpectedly promoted Wei Yan, which shows that Liu Bei trusted and relied heavily on Wei Yan. Wei Yan did not have any backbones behind his head, but he was "extremely evil in temperament" and was not good at dealing with people, Zhuge Liang once rejected his "Meridian Valley Plot", and Changshi Yangyi was in the same situation as him.
For some reason, before Wuzhangyuan's death, Zhuge Liang seemed to be a little suspicious of Wei Yan, and announced that his will would exclude Wei Yan, so that Later Yang Yi seized the opportunity to eliminate Wei Yan in the name of "plotting rebellion". Wei Yan's death was undoubtedly a great loss to Shu Han, and after that, "there were no generals in Shu, and Liao became a pioneer"!