You can work on a project, or you can work on a tool to make that project easier. A work-station, a jig, a library, a pod orchestration framework. Sometimes the new thing you've made will make the target project easier; sometimes you go down a rabbit hole and forget the project you were supposed to be working on as you start designing a new language to write a library in to write a database with that would suit your new project a lot better than SQLite.
Open any wood-working magazine, and half the projects are workbenches and shop organization.
I always thought old hand tools were kind of crap to use though until I cleaned up an old block plane and sharpened the blade. With a sharpened blade it made incredibly satisfying curls of wood on my next woodworking project, where I would have normally used my loud and unpleasant belt sander. I think I get it now why some people really love collecting old tools.
All of the above is fine, learning the history of and techniques in restoring things is cool.