Yes it will. However, the rated lifespan quoted for LEDs is the time taken to decay to 70% - more than 10 years.
Other lights also decay. For instance CFLs gradually lose output over a shorter period of time (in some cases Putting in extra lights is not the solution.

Thank you very much, David.

I agree putting in extra lights is not the solution. Most LEDs are rated from 25,000-100,000 hours at L70. L70 is a 30% decrease in light output. The human eye can start to tell the difference when the light has dimmed 30%. This is reason why L70 (lumen depreciation to 70%) is important.

John Cambruzzi
Certified Landscape Lighting Specialist