Curly hair that afro originated peoples have such a characteristic causes very difficulties in harvesting with both FUT and FUE techniques. But a experienced hand may have ability to  done  succesessfull harvesting  for such hair  which needs 2500- 3000 grafts in one session. Most important point is dept of hair follicles that changes from person to person and we can not understand the dept of hair follicles before starting the harvesting procedure. If the hair bulb seated very shallow, it will be very easy to get out those grafts for us; if bulb is seated very deep and curl is acute angled harvesting period would be non productive..