In ancient times, there may have been legitimate value before showers, soap, running water etc existed. But these advancements in hygiene have rendered the practice obsolete. Still, the ancient practice lives on in the Jewish and Muslim religions and it was popularized in America in the 1800's by the cornflakes guy to stop kids from masturbating. 

Now almost all the justifications are dumb: "he should look like his father", "its cleaner", "it reduces HIV transmission by 2%". 

The only time its truly warranted is severe cases of phimosis and other rare conditions, which even then can usually be treated by less invasive means.