Unhappy surprises can come in all sizes and shapes. Sometimes there is more than one way to design a product, and not all designs for products are equally safe. The manufacturer of a product can be liable (responsible) for the injury caused by that product if it was not properly designed, manufactured, or assembled.
Good examples of this are some airbags and seatbelts in automobiles. Airbags meant to insure lives were actually deploying in such a way that they caused serious or fatal injuries, sometimes deploying after only a minor bump. Seatbelts were at times causing abdominal injuries. The “cure” was never meant to be worse than the cause.
Manufacturers cannot always predict what possible injuries might occur. But there have been times when they have known in advance that injuries might be caused by a design flaw and yet proceeded with that product design anyway. When this occurs, manufacturers and designers, and anyone else who participated in putting a faulty design on the market, should be held accountable when it has injured an innocent party.