High-brightness LEDs for solid-state lighting can last 50,000 hours or more, but the components surrounding them generate heat that can cause early failures. The early failures can be seen on many LED products, especially the cheap ones. Lighting products have historically been reliable, but as electronics-rich CFLs (compact fluorescent lights) began to replace incandescent bulbs, consumers began seeing the products’ early failures. And the same is expected to happen with many LED designs.
Product lifetime and product reliability are different things. Lifetime refers to the length of time an end user can expect a product to work. Reliability refers to how many products per thousand a user can expect to fail in normal use during their expected lifetime. LED component manufacturers often quote lifetimes of 50,000 hours or more for the LED itself, LED because the lighting unit comprises of also many other parts (LED driver/power supply), the actual lifetime of the unit can easily be considerably shorter than the lifetime of the LED itself.
Burn out: Weak links affect HB-LED lifetime article tells that proper selection of capacitors and other components, along with thermal management, can help you save your LED lighting product from an early demise.