It doesn't work like that. Testing doesn't enumerate the physical design space. It only enumerates a model. Only very simple theoretical models can be enumerat

It doesn't work like that. Testing doesn't enumerate the physical design space. It only enumerates a model. Only very simple theoretical models can be enumerated in practice. We have to design with much more sophisticated and accurate models that can't be enumerated, and we have to settle for knowing that even those models are inadequate to describe everything we need to account for. We do our best to design in a way that makes the simple, testable models valid and informative, but it's impossible to completely succeed, so we only ever test "enough" (to make money).