The same student exists three times in the institute's records

A student takes a foundation course, then adds a test-preparation batch. Because enrolment is per course, they are entered again — often with a slightly different spelling, which guarantees the two are never matched.

What breaks quietly

Dues are chased twice, sometimes with different figures. Attendance looks worse than it is because it is split. Headcount overstates the student body, which matters when the institute is planning capacity or telling anyone how many students it teaches.

Family, not student

The unit that pays is usually the family, not the student. Institutes that group by family find that a meaningful share of their receivables belong to a smaller number of households than they thought, which changes how collections are approached.

Fixing it later is much harder

Merging duplicated histories after two years of fees and attendance is genuinely difficult work. Enrolment structured around one person with many enrolments avoids the entire problem at setup, and costs nothing at that point.