I thought LED bulbs were supposed to last for many years. I put on in my
barn about 2 years ago. It's on all the time as a safety light. It only
uses about 5 watts so I'm not concerned about energy usage. (25W
equivlent).

All of a sudden it has gotten real dim, and it flickers. I'm wondering
what caused that? I know it cant be fixed and needs to be replaced, but
I did not think the LED bulbs were supposed to fail for many years.

When I shut it off, it stays lit for a few seconds after the switch is
OFF, so I imagine there is a capacitor in it, but obviously that cap is
working..... But it's less than half as bright as it used to be, and
flickers.