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What is the distribution for failure rates in LED lights. Is it a event function long a Poisson curve?
50 or a 100 thousand hours are great. If you are >+4STD in the quality control area. But if the bulb fails early you are hosed. This is the tradeoff we learn from 6-Sigma; the cost to push from 5 to 6 sigma can be almost asymptotic for certain processes. And since no one will pay for that the actual failure distribution is far less than 5 or 6 STD, often less than 4, which sounds great until you churn out a billion units of something.