Bukhari

Hadith Commentary:
Because by growing the moustache, a person becomes unsightly and formidable in appearance, resembling the form of a bear, and while eating, all the hairs of the moustache mix with the food, and this is a kind of filth. However, nowadays, fashion enthusiasts have adopted this very bear-like fashion and have thus assimilated their appearance with that of beasts.

12. Commentary:
➊ Removing the hair below the navel is included in the natural disposition (fitrah) because, during intercourse, long hair can become contaminated with impurity. Cleanliness would be difficult, especially when water is unavailable or scarce. Therefore, shaving them is necessary in order to avoid impurity and foul odor.
➋ The word "halq" (shaving) has appeared in the hadith, but there is consensus that these hairs can be removed by any method—by shaving, applying a depilatory agent, plucking, or cutting. However, from a medical perspective, shaving is most beneficial. It increases or maintains sexual vigor, and this ruling applies equally to both men and women.
➌ Only the front private part is included in the term "private part" (sharmgah), although according to some scholars, both the front and rear private parts are included. And Allah knows best.