Products of all types - cars, incandescent bulbs, your iPad and iPhone - are designed with planned obsolescence in mind. The need or desire to replace products quickly and a shorter product life-cycle are a consistent drain on wealth. In the previous generation, the latest television sets were big household expenses, just like they are today, but they stayed operational and sufficient for a couple of decades.
Today, I don't know anyone whose main television is older than five years. And with new technology continually entering the market - high-definition, internet connectivity, LED backlighting, 120, 240 or 480 frame-per-second interpolation, applications, 3-D, wide color gamut, and 4K - salespeople always have a reason to convince consumers to upgrade. The older relatives of today's technology still work fine, but this is the core of planned obsolescence. Products are designed in a way that consumers don't want to keep the old.
The automobile industry is a great example. Every year, manufacturers release slightly updated versions of the same cars that have a slightly updated look and feel. The body is a little sleeker, a signature feature is more pronounced, and the dashboard technology is a little more advanced. What was perfectly modern last year is now stylistically out of date. There can be a social stigma to owning a product that isn't the latest iteration, and this encourages consumers to spend more money.
There's nothing wrong with boosting the automobile industry or lining Apple's pockets with cash. It helps the economy. But if you're doing so to the detriment of your own personal finances, take a minute to evaluate how you've been psychologically manipulated into spending your money. Although I had the same mobile phone from late 1999 when I purchased my first to about 2003, when my finances had improved, since then I've regularly upgraded every twenty-four to twenty-eight months.