SunWorship
Established Member
3 years at 12 hours a day would only be just over 13,000 hours. An OLED can do that without much degradation (any TV will degrade though). As long as you vary content I wouldn't worry.
Take a look at the screen grabs dataset in the RTINGS burn-in test. Subtle burn in is evident after just 8 weeks or 1120 hours of FIFA gameplay. Newer tv’s are more resistant to damage but the pictures don’t lie: this is a fragile technology.