Studies have shown that re-reading notes immediately after class improves ones ability to retain information. Therefore, it is important that neither party be without a set of notes for a long period of time. Students who typically need note taking assistance often wish to remain anonymous. Some may have an obvious disability, while others may not. It is possible that a note taker may never know who the student for whom they are taking notes is.
Confidentiality is of the utmost importance.
May not be a visible problem. Side effects of certain medication may make note taking difficult. Health-related absences may occur in which case it is appropriate for the students to be able to copy notes for classes missed. There are different degrees of visual impairment. Assume the person can see.