As far as why, there are a few basic reasons people may choose to do a subincision:

• The procedure can be done for the pleasure of the recipient, as the inside of the penis often feels better than the outside — and even if it's not specifically "better", it definitely exposes more nerves to direct sexual contact.

• It can be done for the pleasure of the recipient's partner — the penis becomes wider and more textured, and can change form slightly during sex. One woman described it as if waves were moving up and down the bottom of her partner's penis during intercourse. In addition, by rubbing the subincision over the clitoris, it allows a woman to come "inside" a man's genitals.

• Some people do it for simple aesthetic or fetishistic value, either because they like the way it looks, or for reasons such as the philosophical concept of removing urination from the shaft of the penis (relocating it to the base) makes the penis purely an organ of pleasure.