The average lifespan of an LED at maximum or close-to-maximum brightness is 40,000 to 60,000 hours, or 4.5 to 6.8 years. So, if you want to increase that lifespan, just turn the backlight down. When they're first set up out of the box in your living room, TVs are usually in "Standard" or "Energy Saving" mode, which generally doesn't look as good to people as "Vivid" or "Dynamic" mode. But the reason Vivid or Dynamic mode generally looks best to people is because it's a preset that maxes out the TV's Backlight and Contrast settings, making it brighter and perceptively more colorful. Unfortunately, not only does that mode tend to obscure picture details and tire your eyes out, it wears out the LEDs in the TV more quickly.