There are many reasons why things fail. Some failures are due to design and manufacturing defects, while others occur because of misuse or abuse.
Some common causes of product failure include:
Poor design - Poorly designed products may fail more frequently than they should. For example, poorly designed river bridge supports may collapse during heavy rains.
Manufacturing issues - Manufacturing problems such as poor quality control, improper assembly, and lack of proper testing can lead to defective products.
Product life or time-related - Some products have a limited useful life. They may become useless after a certain amount of time. For example, a rechargeable battery becomes useless after a certain number of charge cycles, or the car tires wear out after a certain number of miles driven.
Improper installation - Improper installation of products can lead to problems such as leaks, cracks, and poor performance.
Improper maintenance - Improperly maintained products may fail sooner than they would otherwise. For example, poorly maintained engines may need replacement sooner than they would otherwise.
Misuse - Misused products may fail more quickly than they should. For example, the use of a product outside of its specifications, failure to follow instructions or using a product in ways that were never intended.
Abuse - Abusive use of a product may cause it to fail earlier than it would otherwise. For example, the abusive use of a lawn mower may shorten the blade's life.
External factors - External factors such as vibration can affect the longevity of a product.
Environmental factors - Environmental factors such as temperature extremes, humidity, dust, dirt, and moisture can affect the life span of products.