When I was at university (5 yr course with a year in industry, so 4 yrs of teaching) I never missed a single lecture, seminar, lab or tutorial. If it was on the timetable I was there. We had large contact hours (engineering degree, so about 25 hrs per week) so was quite a lot to fit in.
I’ve told this to a few people over the years when the topic comes up in conversation. No one has ever believed me, and it’s not something I can prove or disprove either way!
Anything you have done in the past that no one believes and you have no way of proving?