As a black car owner I could spend my entire life cleaning the car, so I do a big job every six months (clay / paint cleanser / polish / sealant) and then 2 bucket every 2 weeks. I hate it, all the effort for such limited gains. Summer is flies (and rain), winter is rain and mud. For me the time is better spent on holidays / mountain biking / seeing friends / listening to music on big home hi-fi / track days etc.... In fact I think I'd rather shut myself in a cupboard for an hour than clean a car as the investment can be incredibly short lived!! That said, for that few minutes before the dust settles it is incredibly satisfying to look at the results. Maybe I need a machine polisher.