(Concern) Parents of sons' worries

I think this is a concern for parents when their children reach higher grades. I feel the same way.

He is an elementary school boy in upper grades who has not undergone circumcision. When he was younger, he didn't manage himself properly, and the foreskin's front part would turn red or he would feel discomfort. Applying medication purchased at the pharmacy helped improve the condition after a few days. As he got older, his management improved compared to when he was younger, so he didn't experience significant inflammation or abnormalities. Among people around him, many children of acquaintances haven't been circumcised, and some say they won't do it. Others mention that it should be done during childhood because doing it later in life can be more painful and difficult, and it's better for hygiene. Circumcision is usually performed when a man becomes an adult if natural circumcision (natural foreskin development) doesn't occur naturally, right? In the past, circumcision was common and culturally standard in Korea, but recently, the trend is moving away from it... Still, mothers of sons have many concerns. I heard that circumcision is not performed in many other countries, but it is still common in Korea and China. My question is: does natural foreskin development generally occur in all adults? Is circumcision performed when natural foreskin doesn't develop? Also, when is the best time to undergo circumcision? I want to know if it's better for hygiene to have it done, or if it's okay to leave it if proper cleanliness is maintained. I'm really contemplating these questions.