The reason why this happens is that every time the emperor goes out to war, it is basically the most critical time for the country or the morale of the soldiers in the country is very low. At this critical moment, the soldiers are in urgent need of someone to inspire them, so the national leaders will personally go to the battlefield to supervise the operation. It can be inferred that even the old emperor, from the original intention, is actually unwilling to go to war. After all, the battlefield is very dangerous, but the reason why they want to go is to boost the morale of their soldiers.
Because if they don't go, the soldiers at the front line may be beaten like that, so in case it really happens, the emperor will go to the battlefield to protect the throne.
As we all know, Judy, as the third emperor of the Ming Dynasty, personally led troops to defend the capital, and the background of Tianzi's family protection was that the northern minorities attacked the city below. It can be said that when the country was in danger, the Emperor of Heaven had to go to the battlefield himself. Although he is very old, he will go to war. However, the son of heaven's expedition is only symbolic, because he can't appear at the front.
But as a leader of a country, it will give great encouragement to the soldiers. This will also make the soldiers feel that the emperor is also very kind to them. In this case, the soldiers who fought on this front will also perform well. Maybe one of them will be appreciated by the emperor and promoted to the rank of emperor.