I bought a treadmill to go under my desk so I could walk while working sometime in the middle of 2020. This worked for about a month before the motor seized and I returned it for a replacement. This one was about the same, then I returned for a refund and bought another model altogehter. This one worked for like 2 months or so before it burnt up, this time they sent me a replacement motor. The replacement motor lasted about another 2 weeks and it died, then another replacement motor, same thing. The third replacement motor literally burned up during the first 30 minute walk I did with it. At this time I had figured out that they were overheating so I shortened my walks and took off the top cover, and had a fan blowing into the air to try and cool it off. After a long back and forth they finally sent me another treadmill altogether, and this one I just gutted.
The final result is the motor has heat-sinks all over it and I have a dryer-vent fan blowing directly into the fan for the motor. It still gets hot and I can tell that it is degrading, at this point I can do 20 minute walks before it starts getting really hot. So now, I just do 5 20 minute walks a day to get to my normal 5 mile goal.
Maybe I should just buy a really expensive treadmill? It would probably have the same issues.