I assume you don't mean Beagle 2.

A Mars rover is a bad example here because it's not an item that is, or will ever be, mass-produced.

how much did the rover cost?

Hard to know, looking at the 600 page NASA PDF, but Google says 400 million. But that's for a object that had to be transported to mars first. I bet transporting a dishwasher to mars intact to sit and not work is a similar amount of money.

Guess I just need to start an appliance company and fail to become enlightened as to why my desire of quality and serviceability are unattainable ideals.

Incidentally, your comment on price is a weak argument, because the product doesn't even exist. Even the luxury appliances have tremendously low longevity now. So luxury at this point basically means it looks really good while it works and you can afford to buy another when it doesn't.