Certain sizes are cheaper than others as they are the more popular sizes. As others have said, the quality of the TV could be the lowest quality, even for an "HD" TV. When I bought my 40" TV, I was debating over getting this HD Smart TV over getting a better quality 1080p TV for double the price. Since I was upgrading from a real old analog TV that had the huge plastic casing and weighted a ton, ANY upgrade in quality would be better than I had. So, did I really
need 1080p for double the price?
I decided to just get the cheaper HD Smart TV. Some of the reviews warned that the picture is great, but the SOUND was horrible. I should have heeded them. The speakers are on the back of the TV, so the sound goes out in the wrong direction than a front facing speaker.

To add on good speakers, I will have to invest another $200 for decent speakers.
Yet, it turns out, it's a good thing I didn't get the 1080p Smart TV after all. The technology for ALL smart TVs changed & upgraded the following year. If I want to use any streaming/casting service, almost all of them require TVs made in 2014 or late. My TV is a 2013, and the apps will not work with it even though it is a "smart TV." The software inside is NOT upgradeable.

I have to do a workaround, like stream/cast from my computer or smartphone using an HDMI cable or dongle attached to the TV and just use the TV as a large screen monitor.
OR, of course, buy a newer (cheap) TV with newer Smart TV software. So no more buying expensive, top of the line TVs or computers or cellphones for me. The technology changes too quickly to be paying high prices. The cheap TV in the OP that may only last 2 years - well the technology may change in 2 years anyway, making it obsolete. Better to throw away an $89 TV than a $500 TV. (Although not better for the environment.

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