Every class is about life skills. Some teachers do adjust grades while others do not. That is, I admit, much how life works. And some students are far better at playing instructors, just as those students will be better at office politics. We cannot control the fact that life is not always fair, but we can try to make our classrooms as fair as possible.
Since I teach composition and rhetoric, I’m already in a subjective domain. No matter how much I count grammar and spelling, my analysis of a paper is largely subjective. The primary “objective” measure I have for a paper is if the student attempted the work. Because I do count things that can be objectively measured, and usually find that these measures correspond to the grades I give in the subjective areas of the course, I seldom doubt my grading.
If you do poorly on simple quizzes and basic homework tasks, you probably do not care about longer papers. If you do not outline a paper, submit drafts, or participate in workshops, it is a reasonable bet that your paper will not be as good as those of students working through the “process” of composition.
So, when a student tells me that my grade was not fair, I can show him or her my grades and ask, “Why didn’t you do well on the quizzes? Why didn’t you participate in peer editing sessions? Why didn’t you care until the last week of class?”
A 79 in my class can indicate a struggling immigrant worked a lot to succeed or that a gifted writer didn’t try very hard. It is a matter of perspective.