There are various ways in which consumer products can be defective or dangerous for their intended use. Flaws in the design of a product may make it inherently dangerous, while inadequate warnings may expose consumers to unknown dangers. Products that are properly designed and have appropriate warnings may still be found to be defective if they are improperly manufactured or damaged in the manufacturing process.
A defect in manufacturing is present when a product fails to meet its intended design even though it was prepared and marketed appropriately and with reasonable care. Manufacturing defects are often subject to strict liability. Essentially, the care applied by the manufacturer in designing the product, choosing the materials, and implementing quality assurance measures is irrelevant. If a product has a manufacturing defect and injures a consumer using the product for its intended purpose, the manufacturer will be liable for the injuries.
Consumers often find that manufacturing defects are hard to prove. This is due to the presence of other contributing factors such as the consumer's conduct, the malfunction of unrelated parts of the product, or difficulty in assessing what actually caused the accident or injury. This can be alleviated to a certain extent by the malfunction doctrine. This doctrine states that if the circumstances of an accident indicate that it was caused by a defect, the ruling out of other causes can establish causation even if the product is severely damaged.
Manufacturing defects, however, are typically rare in the realm of products liability, as they affect a limited number of products, and the defective products can often be replaced. Those injured by what they believe to be a defect in the manufacturing of a product may consult a personal injury attorney to evaluate the circumstances of their case and acquire the necessary evidence to prove their claim.
Source: Findlaw, "Defects in Manufacturing," accessed on Sept. 27, 2015