Before I started writing, I couldn't imagine a writer working on more than one story at a time. While I had no idea of the actual scope of efforts and time writing demanded, I knew it was at least "a lot", and it didn't possible to stretch one's mind on two or three projects at once.
Fast-forward a few years later. I started roleplaying and realised I could hold more than one story in my head at once. It still wasn't writing, but I think life was trying to prepare me for the truth.
Today I alternate between six different WIPs. I tend give most of my writing time to one of them during a few months, with the occasional dabbling in another. Then the first is put on the backburner, the second becomes the main project, and a third takes the dabbler's place.*
I know, however, that not all writers work like this. The number of WIPs one consistently works with is like most other variables of the writers' journey: they vary from one person to the other.
So I'm curious, writer friends! How many WIPs do you work with? If you've got more than one, how do you usually function?
*Trying to pick the next dabbler is always tons of fun... in a very *head desk* I don't know which I prefer right now, aaaah!