IMHO, LED lights are like any other electronic technology....or anything other technology period. One must expect and prepare for an eventual failure of some kind.If they don't fail then great, but if they do, have the LEDs designed so they can be replaced easily. Treat them almost like you would any other light bulb - with the expectation they'll need to be replaced, and design as such.
Someone on SSP once mentioned LED issues at Arriva, and how difficult it was to replace the faulty LEDs, to the point that they left them be.