(Not making this as an edit to my previous post because it's kinda a completely different point)
So, for reference, I am currently involved in 2 collaborative projects in their VERY early stages. (technically 4 but the other two are honestly mostly just me.)
The first is one with a close friend of mine. They are the "writer" and I am the "artist". Our roles are a tad murky because they helped me develop the visual style (MOSTLY EDITORIAL WORK MIND YOU) and I've helped structure the plot and have offered feedback on some of the scenes. Thumbnail work will most likely be split between the two of us. My reasons for taking on this project: 1) I really like my friend's writing, they do stuff WAYY different (Keyword different) than what I write. This project is an action/drama thing which is something that I don't think I could handle as well as they can, but I'm REALLY excited to draw some fight scenes and experiment with more dynamic panel structures. Even though I will probably be doing most of the work, the work is something that I'm interested in and would not otherwise be able to do on my own.
The second is one with my girlfriend who has had an idea for a big fantasy story in her head for years but hasn't been able to form it into a cohesive story. In this project, I am the "Writer" and she is the "Artist", however, I am working with her ideas. Even though I am "writing" this project I would totally not feel comfortable taking credit for it, especially because it's her ideas, and again, mostly her work, going into the project. If it gets finished I probably wouldn't feel comfortable having my name on the project, just because realistically I've done so little work compared to her. And PLOTTING/STRUCTURE ARE THE HARD PART OF WRITING. What I'm getting out of this project is I get to 1) help my girlfriend do a thing she's always wanted to do 2) I get to write a "lighthearted" fantasy adventure thing that I otherwise wouldn't do because I'm not really interested in drawing that sort of stuff. It's a fun experience for me.
In the future, there are some people that I know that I would love to collaborate with if we ever find the time outside of our own personal projects, because I think together we could really ELEVATE each others work and bring out aspects of each others style that wouldn't otherwise come out on our own.
Note that (and this is just me) my reasons for doing any of these projects has NOTHING to do with exposure/money/fame. I can do that on my own just fine, and I assume most other artists in a healthy collaborative project have MOSTLY personal reasons for wanting to do the project.