Here are some things to consider:
* Personal preference: Some girls prefer the feeling of being completely smooth, while others prefer to leave the hair natural.
* Hygiene: Some believe it makes hygiene easier, while others find it doesn't make a difference.
* Comfort: Some find that shaving prevents irritation from underwear or activities like exercise, while others experience irritation from shaving itself.
* Cultural norms: What's considered "normal" varies across cultures and social circles.
Ultimately, the decision is up to the individual and what makes them feel most comfortable and confident. There are no medical reasons to shave, and it's perfectly healthy and normal to have hair on your bum.