The first advantage is that the sensation. The foreskin is a comfortable fitting, soft cloth on the face of the penis, providing friction for nerves. There is also a far longer penile shaft to supply greater sensual feeling. Both encounter more sensitivity together with the foreskin.
Natural antimicrobial fluid lubrication adds to the sensation. A man’s sperm travels around the shaft while it is still partly within the vagina. This gives you a better opportunity to reach that orgasm. It’s …