In economics and industrial design, planned obsolescence (also called built-in obsolescence or premature obsolescence) is the concept of policies planning or designing a product with an artificially limited useful life or a purposely frail design, so that it becomes obsolete after a certain predetermined period of time upon which it decrementally functions or suddenly ceases to function, or might be perceived as unfashionable.[1] Once regarded as a conspiracy theory, the rationale behind this strategy is to generate long-term sales volume by reducing the time between repeat purchases (referred to as "shortening the replacement cycle").[2] It is the deliberate shortening of the lifespan of a product to force people to purchase functional replacements.[3]