Make it so reliable that no dust, dirt, crumbs, water, etc can get into the mechanical components / PCB / housing, etc?
If there is a way to do that, how expensive would it be to implement on a mass production scale?
I know there is relatively cheap ways to water proof the PCB with nano coatings.
But that doesn't cover the mechanical switches, there is always that gap on top of the switch for stuff to get into the inner mechanical workings.
Any ideas from the folks here?