Why it happens
1. You count overall, not per course
Most colleges apply the rule course by course. One bad subject can block you even if your average looks fine.
2. Labs and tutorials count separately
A missed 3-hour lab can count as one class or three, depending on your college. Check how yours counts them.
3. You find out too late
By the time the shortage list comes out, there aren't enough classes left to recover. Track it weekly instead.
Fix it now
Use the free attendance calculator. How many classes can you skip and still stay above 75%? Answer in 5 seconds.
Fix it for good
Life Archive for Students by golash (launching soon): Add your timetable once. Track attendance per course in one tap, keep every deadline in one inbox, and see where your week actually went.