I go through multi-year periods of acquisition, trying different stuff just for the unique user experience, not because of need. Then in one season or two I'll do a quick purge, overshooting the purge as much as I do the acquisition. A lot of film stuff has gotten so inexpensive, it's not to-terrible an issue. Anyway, you gain the experience to speak authoritatively on different equipment, from a Contarex to Leicaflex. You get the idea. The process does refine in your own head what you "need", "want" "like" ect.
Recently, over the last 6-8 months I sold all my rangefinders. A mistake to sell "all." Variety helps keep things from getting stale. So, I'll probably start the pro=cess over again. It's sort of a game.
My main cameras and lenses, that I use most of the time, don't get sold. Too many memories attached to that metal and glass. It's all the periphery that gets bought and sold.