Some wear them to play up the outfit they are wearing,some because it is part of their tradition,like certain royal families had family crests colors that were strictly for their families,commonality doesn't play apart of certain accessories,then again you might have two women from different parts of the world in the same store liking the same earrings,or ring.
I wear the basics,my wedding band,a pair of earrings to match the colors of what I am wearing,and a watch that might be similar to the colors I have on,sometimes a brim(hat).and gold chains around my neck,and a bracelet or two.
In the Medieval days only the Kings and Queens and all the influential people use to wear accessories because they were the only people that could afford it and it was a sign of how rich they were. (Why because all of it was made of real gold en expensive gems). Every culture got a different way of making and wearing their accessories.
I only wear gold because I'm allergic to anything ells. I don't like to wear a lot of things a the same time so I'll wear a necklace, earrings and two rings that match at the same time
People wear accessories to look good. Like ladies wear bangles, bracelets, earrings and so on. Similarly boys also wear rings, bracelets etc. Ring is the only accessory which is used in almost all cultures. As a lady, I love to wear rings, earrings, necklace, bracelets and I have huge collection of bangles (some of them are hand made; made by me ;))
have a nice day and enjoy blurting.
People wear accessories to offset, or compliment their clothing.
So they could look nice and impress people by expressing them-self.
To show of their money lol
We wear it to match it with the seasons. We men and women are causal. But there are some accessories that is elegant but expensive.
I think is to show how rich they are and that they can were it with what ever they want.