Why? How unfair?

This has something to do with regional differences. Different regions have different levels and intensities of education, and even different ways of education.

And an exam can't explain the problem, maybe it's a play or a topic that doesn't taste good.

Besides, people are recruited according to proportion and quota. For example, if Tsinghua wants to recruit 100 science students in Hunan, he will directly look at the scores of the whole province 100 and then throw them away. So the score of grades is a relative concept.

What remains unchanged is your excellent ranking in your region.