When a product is defective, it means that it is imperfect in some way. Perhaps the connection to the battery is poor, so it won't start up. Maybe the medication you ordered was contaminated.
Defective protects can become a huge hazard in your home. For example, a device like a pressure cooker with loose latches or no way to release pressure in an emergency could explode and cause harm. A coffee pot that doesn't regulate itself correctly could spray hot water or coffee on those around it.
We rely on companies to make good products safely for consumers and neighbors alike. Tennessee has seen some dangerous product lawsuits over the years, but one of the state's largest liabilities may be industrial interference in its precious water resources.