When I began to consider being circumcised, the doctor told me that a benefit to being cut was that the the lack of the foreskin covering of the glans would toughen the tissue (skin) of the glans. Evidently, that was one of the ancient reasons for circumcision. It would make the glans skin impervious to the syphilis spirochetti being able to bore through the toughened tissue covering the glans. Syphilis is spread usually by intercourse with a diseased person, not by unclean hands. But that is one example that the glans is open to disease through contact. Another is gonorrhea that infects the urethra through the "slit " opening. Good reasons for using condoms.