It was many years ago. I realised one of my teachers wrote strange abbreviations in my exams, but I could never find out what they meant.
When I deliver the exams I have corrected back to my students, I always have the sentation that they return them to me and they don't know why their answers are wrong. I sometimes think they complain about silly things.
If they stopped to analyse their answers and why they are wrong, very probably, they would have good reasons to complain.
What I did is, I created a number of abbreviations I could easily write as corrections and If agreed with my students, they would understand why they made mistakes.
Marking Written Exams
Cheers for now.