I mean, few things in life can be graded objectively so that's not really the best standard to hold education to. There's a lot of value in learning and practicing the skill of taking in information and then rearranging it into your own words, creating and supporting arguments from the knowledge you've gained.

But the subjectivity of it DOES mean that occasionally teachers will need to set aside their egos. Those who legitimately want to educate the next generation usually can do that, but some just enjoy having power over children and absolutely will not units forced to do so (and doing so will just create a new grudge against that student).