My graduate student days were fun — most of the times.
I had 3 different professors — in 3 different semesters, when I was their teaching assistant (TA).
None of them was any acerbic to me ever, even when I would be at fault.
Guy Indebetow was the very first one. A cheerful person and very friendly. He would say — in spirit, not necessarily all the wording, “I would not interfere in how you grade the students, but wisdom says you give them a little lose marking, if anyone comes with any grievance though, I would redirect them to you.”
It so happened that the only students that would come banging on my doors are the ones who would often just seek some more marks, than “deserve it”. — I am not speaking from their POV though, I wasn’t taking theirs — you see.
I remember two cases.
A student who was originally from Pune. He would come looking for some marks.
Me: I am sorry you don’t deserve more here.