I roleplay for a lot of reasons

For one it's downright straight fun, no pressure writing. There is no pressure to plan everything out by myself and proceed to write and direct everything by myself.

For two, it's a way for me to make the stories I will not find anywhere else. (or very rarely) As I normally RP queer women romancing other queer women, it's me creating my own representation for myself (as a queer woman)

For three, I make friends through my RPs. I love interacting with my partners and building a friendship if I can. Some people I don't bond with and we have a 'business' relationship. But I do try to make friends.

For four, I love immersing myself in my characters minds and thoughts and feelings. I go through ups and downs with them. Their friendships. Their enemies. Their lovers. I feel as they do. 

There's probably more but those are the first four that cross my mind at the moment.