During the period of Yang Di and Emperor Wu of the Han Dynasty, although they both made great achievements through the ages, the final outcome was quite different. The reasons behind this difference are complex and diverse.

First, the two men had different historical backgrounds when they became monarchs, and they took over in different periods.

Yang Di took over the Sui Dynasty. At that time, the Sui Dynasty had just annexed the Chen Dynasty, and it was relatively stable when it was in the hands of Emperor Wen. However, seeing his father's achievements, Yang Di also took Wendi as an example and thought that he could do what the former could do, but this was not the case. After all, the foundation of the Sui Dynasty was not stable, and he still needed to make greater efforts. For Emperor Wu of the Han Dynasty, when he took over the Han Dynasty, the foundation of the Han Dynasty was solid enough, which was very beneficial to the succession of Emperor Wu of the Han Dynasty.

Second, different judgments and choices about the situation will affect the historical trend.

Yang Di misjudged the situation in the Sui Dynasty. At that time, the Sui Dynasty was not yet stable, and he was eager to expand his territory and territory. He just ignored the judgment of the status quo of the Sui Dynasty, and just indulged in trying to annex other countries with his predecessor, instead of focusing on stabilizing the status quo, which also became a precursor to the final result of Yang Di. Emperor Wu of the Han Dynasty is different, because the current situation in the Han Dynasty is very beneficial to Emperor Wu of the Han Dynasty, which is completely conducive to the display of his talents.

Third, they have different personalities and different strategies for governing the country. Even though both of them have certain achievements, they still have different opinions.

After all, life is a distinct individual, and a person's personality must be a personal thing. Yang Di and Emperor Wu of the Han Dynasty have completely different personalities. Of course, their personality will more or less affect their ideas and strategies of governing the country. But the reason why they have different evaluations in later generations cannot be completely attributed to their personalities. Objectively speaking, this is related to their historical background.