(New Player) What is the point of prestiging a character past 3?

I used to play DBD a good amount when I was younger but never picked up on any hard mechanics or anything before I stopped playing, and I only just recently got back into it and I’m doing pretty well, I understand what makes good perk builds, I’m going for the perks I like and experimenting with gameplay.

The only thing I’m confused about that I can’t understand as easily as much of the rest of the game is—why go past prestige 3?

I understand prestige one on a character let’s you share their tier 1 perks automatically and you can even still upgrade them through other blood webs, I understand going to prestige 3 just so that you always have the tier 3 perks automatically, but what’s the point after that? I get that maybe items, but prestiging just once can get you enough items, add ons and offerings to last a good while. So aside from maybe getting just a lot of items and stuff on one person, what’s the point? Cosmetics? Just to be cool? I just don’t get why so I wanted to ask any more experienced players.