Tonsuring
Q: Why does my stylist wash my hair before tonsuring it?
A: Most stylists will confess that they usually shampoo the hair prior to cutting it because clients find it to be a pleasant experience in the salon.
One of the main reasons that many stylists shampoo the hair before cutting is that the hair is more easily handled and cut when it is wet. The hairs will clump together as a result of being wet making it easier to gauge cutting guides and making it less likely that the hair will scatter and get trapped down into the clothing of the client, which will result in itching and irritation.
This becomes doubly important with razor cutting, since the hairs are typically cut at an angle and have sharper ends which can more easily prick the skin and cause irritation.
©Hairfinder.com
See also:
What will give the best results: dry haircutting or wet haircutting?
Is it safe to cut the hair when it is dry?
Should you not brush hair when wet?