When I wash dishes by hand, I find it pretty calming. Especially after a big family dinner with all the siblings. With all the attendant pots, pans, dishes. I think doing a repetitive task where you have to pay some level of mechanical attention to the task (e.g. hand washing wine glasses) helps free up part of the cognitive overhead that you usually dedicate to 'over thinking, worrying, pondering'. For some, it might not be washing dishes - my sister loves raking leaves - the non leaf-blower - you're never really done because the leaves keep on a'falling way. I think we all know our handful of activities that we enjoy doing - but aren't as fundamental as breathing (where it is kind of like being in an isolation tank - too isolated, pure).