At the same time, my measuring stick is always, "Is the customer happy?" Software will never be perfect, so a zero bug rate is not a reasonable goal. Happy customers is quite a reasonable goal, and when they are not, their concerns direct where you need more quality.
NASA and nuclear power stations have a rather high cost to remediate some software defects, so it makes sense to work much harder to find them earlier. Same thing with anything life safety critical. You can't patch a bug and uncrash your space probe, or unmeltdown your powerplant, or unkill your patient. But a lot of other stuff is ok; yeah, it's not great if music players don't work on Jan 1 of years after a leap year, but you'll have four years for the product to decline into irrelevancy before that happens again (or to get patches out, if Zune had market fit)
> Do you really think NASA software is bug free?
Ignoring the fact you are arguing in bad faith is not compelling
GL with whatever.