do led's have a usable life span?

[gpx1200]

so I have a diy led fixture that I built around 2011 that still has most of it's original led's, I has always served me well but im starting to question the output they have been run for up to 14 hrs a day(RB's) and have not always been the coolest they could have been but I never had one cook on me, my only few failures have been from corrosion. but now they are getting old and the colors aren't looking so great any more...
so for the long term led users, when do you start thinking about replacing them???

 

[gpx1200]

should point out all my led's are cree xp-g and xt-e

 

[cilyjr]

5 to 6 years. I'm gonna slowly change out the pucks in my sols soon. There about 5 years old