I don't have a dedicated work space (not even a proper desk), so I usually can't just leave my art supplies out. But if I could, I would definitely leave out a current project until I'm done with it, which could lead to mess.

In general, I tend to put off decluttering stuff, so things will pile up and I'll do the endless dance of moving stuff to my bed, then back to the chair or other surface, then back to my bed ad nauseam. This usually goes on for a while — weeks, sometimes even months — before I do a full decluttering reset things back to a status quo that's functional. The clutter can start to stress me out and mess with my mental health, so I really should get better at keeping things cleaned up.