Because more than a few people buy something because of it's (low) price. When something is inexpensive, it often has a shorter lifespan and you tend to replace

Because more than a few people buy something because of it's (low) price. When something is inexpensive, it often has a shorter lifespan and you tend to replace it more frequently than you would a more expensive item. Admittedly 1) not everyone can afford something pricier, and 2) higher cost doesn't always mean better quality. On top of that, if manufacturers made things that lasted forever, they'd go out of business quickly. Who'd buy a replacement, or something newer, if item X is still going strong after 10 years or more?