Defective Products are those that have flaws making them dangerous to use as they were designed. These happen when the manufacturer fails to do proper testing for quality control and fails to meet its own standards.
Defective Products cases are based on negligence by the manufacturer and breach of the implied warranty of the product. Negligence by the manufacturer comes from the failure to meet standards and to do proper quality control testing. The breach of the implied warranty comes from the belief by a consumer that the product will not cause them harm when they use the product as it was intended to be used.
The manufacturer has a duty to use ordinary care to make sure that the product is reasonably safe for the use that it is intended. The manufacturer does not have a duty to make a completely safe product, but to make the product safe for the intended purpose and to warn consumers of potentially hazardous components of the product. The manufacturer is not responsible for injuries that come from consumers using the product in a way that is outside the ordinary purpose of the product because the injury is unforeseeable to the manufacturer.
Manufacturers have a responsibility to test the products they produce for defects that could cause injuries. Not doing so is negligent and creates a products liability cause of action. Manufacturers should not allow consumers to be the test subjects to see if anything will happen.