As consumers we've developed a certain tolerance for defective products. Previous versions of Microsoft's Windows were notoriously prone to crashing - and people complained about it but bought the product anyway. I think finding bugs in the first releases of any hi-tech hardware and software product is expected these days. Even Apple was embarrassed by the antenna problems in the iPhone.
It would be hard to argue that as an employee you should have zero tolerance for defects in your company's products. The law recognizes that some defects 'merely' render a product unusable or partially usable and cause 'only' economic injury (i.e., the money you paid for the product is lost). State's rules vary as to who can recover for economic injury and whether the user can be partially at fault for misusing a product. But from an employee's point of view if you're uncomfortable with a defect that you're aware of, you should make sure that it is documented and brought to the attention of whoever is responsible for quality control, or at least your boss.
Obviously, it's a whole different matter if the defect is one that could cause injury or death to customers. Most companies believe that intentionally killing customers is bad for business (well, except for the cigarette industry), but lethal manufacturing or design defects in medical products, or unanticipated drug side-effects are announced all the time. Even in non-medical industries, like the car industry, product defects can be fatal. If you are aware of a potentially lethal defect, you owe it to yourself, your company and the rest of society to make sure the problem is documented, recognized, and resolved.
