When Liu Bei was chased and killed by the Yellow Turban forces, Zhao Yun fought bravely to protect Liu Bei's safety. However, it has not been reused all the time.
First of all, although Zhao Yun's seven in and seven out successfully protected Adou, in the critical situation at that time, Liu Bei himself had to leave his wife and children and escape. Zhao Yun's duty is to protect Liu Bei completely, but he personally took the risk to save Liu Chan, if Liu Bei had an accident, Zhao Yun would be considered negligent, and his responsibility would be increased. Moreover, this move made Liu Bei lose face in the army. When he was in a panic, he ran away on his own, but his wife and children had to rely on outsiders to rescue him.
Another thing is that after Sun Shangxiang married Liu Bei, Liu Bei put Zhao Yun in charge of internal affairs. However, because of Zhao Yun's negligence, he almost asked Sun Shangxiang to bring Liu Chan back to Soochow. Fortunately, Zhang Fei took action in time to relieve the siege and save the day. Zhao Yun's mistake caused Liu Bei's descendants to be almost taken captive, so for Liu Bei, the idea of trusting and reusing Zhao Yun was questioned to a certain extent.
In the end, in the matter of attacking Jiangdong, many courtiers opposed this action, and Zhuge Liang only tactfully persuaded him. Only Zhao Yun bluntly expressed a different opinion. This will undoubtedly anger Liu Bei, coupled with the fact that Guan Yu, Zhang Fei and other famous generals have a more prominent position in Liu Bei's mind, Zhao Yun looks dwarfed. Zhao Yun's overly upright personality also makes him easy to offend people. Therefore, Liu Bei did not let him participate too much in political affairs after that.