Li Guang's promotion suffered many setbacks. What prevented him from being appointed for life?

Li Guang himself: politically naive (as can be seen from the chaos of the Seven Kingdoms), arrogant and narrow-minded (killing Commander Baling, committing suicide), eager for success (fortune-telling), relying on his own courage (shooting sculptures).

War against Hungary: Li Guang was brave, but it relied on long-distance surprise attack and accurate judgment, while Li Guang repeatedly lost his way.

Policy: Emperor Wu of the Han Dynasty took the initiative to attack the Xiongnu, while Li Guang, who had been the magistrate of the border county for many years, was used to defending, which may not be able to adapt to the new situation.

As Emperor Wen said, Li Guang was born at an inopportune time. Maybe Li Guangfei was a talented general, but unfortunately he didn't have tenure.

As for Emperor Wu of the Han Dynasty, I think he didn't value Li Guang and didn't suppress him. Li Guang went to war several times, but he did not meet the requirements of sealing Hou. With Huo Wei here, Hanwu will never give Li Guang a better chance, which is understandable.