First, Liu Bei himself is introverted.
For Liu Bei, when he was weak at first, he always wanted to hide his talent. Therefore, it is inevitable to be passive towards Nuo Nuo at this time, which makes people feel that he is a scholar and has no future. So many people will look down on him at this time, which is exactly where Liu Bei wants to hide his strength.
Second, Yuan Shu doesn't have the ability to read people.
In fact, people familiar with the Three Kingdoms know that Yuan Shu relies more on wishful command in the course of combat. This is enough to show that he is not good at grasping the ability of talents, so his evaluation of a person will have many biased places, especially Liu Bei. Without Bole's vision, Yuan Shu missed Liu Bei, a swift horse.
Third, Yuan Shu is jealous.
For Yuan Shu, as the commander-in-chief of the three armed forces, his political status is very high. At this time, if he thinks that a person can surpass him or even defeat him in the future, it is obviously not conducive to his own rule. At the same time, he is also a very narrow-minded person. How can Liu Bei, who is generous, not be jealous? At this time, it is very good to just give him a low evaluation, and it is extremely forbearing not to kill him completely.