It's often cheaper for manufacturers of low-cost electronics to minimally test devices before sale, with the expectation that some will die early in their life

It's often cheaper for manufacturers of low-cost electronics to minimally test devices before sale, with the expectation that some will die early in their life and be fixed under warranty. Burning in everything you make is expensive, especially if failure rates are fairly low anyway. Electronics tend to have a bathtub curve of failure, with high failure rates at the beginning of life. It wouldn't surprise me that older CFLs (with much higher market prices) had greater levels of testing/burn in before being shipped, leading to much lower failure rates.