They are designed to die just slightly past the warranty, so they can sell you another. Of course, the statistics means that quite a few units won't even last until then.
Before manufacturing tolerances were as tight, they'd error on the side of caution and overbuild, resulting in a wider MTBF curve. There were both many early failures as well as ones which far exceeded their expected life. Now, the standard deviation is much smaller so the end-of-life has become more well-defined both at the cost of nothing much lasting longer nor shorter than expected.
Before manufacturing tolerances were as tight, they'd error on the side of caution and overbuild, resulting in a wider MTBF curve. There were both many early failures as well as ones which far exceeded their expected life. Now, the standard deviation is much smaller so the end-of-life has become more well-defined both at the cost of nothing much lasting longer nor shorter than expected.