i don't see any lifespan quoted in the product specification page.
generally, LED lifespan can fall if they are over-driven (supplying more amp than its spec says it requires), or overheated.
some manufacturers deliberately overdrive LEDs to gain more light output for a given LED size.
given a typical LED lifespan of 25000 hours = 2.8 years+ of continuous light output, some might feel its worthwhile to sacrifice a bit of lifespan for greater light output.