[Perfectlap]

I agree completely, most high end polishes both clean and protect. But the detailing product companies all want to sell twelve different products to have you believe you will be at a sizeable disadvatage unles you use all of their sealants and waxes etc.
As far as paint is concerned, a good polish and a quick shine spray(I prefer anti-statics) are all you really need to keep the surface shiny and protected year round.
Believe me I have $pent allllllllotttt of time and money figuring this out.
But some people see it as a hobby and enjoy experimentation.