I have a 2016 LG OLED, about 1.5yrs in i started to get burn in images, just feint images from logos like Sky Sports and Netflix that would be visible at times. 2yrs in they were very visible, on anything green (FOOTBALL PITCHES FFS!), red or blue. Now i have these huge fucking wavy lines going from left to right across the whole screen, only visible when the picture is the same colours as above but it's basically meant that watching football is now nearly unbearable. I spoke to Richer Sounds as it comes with a 6yr warranty and the **** cost me 1.5k. They tell me manufacturers don't cover burn in as they say its caused by irregular watching. I mean what a piss take, charge so much for a TV and you're not allowed to watch what you want for as long as you want. The only repair for this is a new screen, which funnily enough you can't find anywhere as a spare part to do yourself and have to send it off to LG, who charge as much as a new TV.
LG are aware of burn in issues, in fact they have put in technological changes into their newer TV's to try and help avoid it where possible, but they deny that it is their TV's issue. I would seriously think twice before getting another one, i needed a second TV and just paid the same amount but got the best LED tv you could buy instead, that won't have this issue.