Cognitive Dissonance
It’s the same thing that makes you pay attention to bad things and mostly ignore good things, whether it be smells, sights, words, people, products…
Good things are just not noteworthy, and your brain loves to keep focusing on the novel/different things which are usually notably negative. You just don’t notice the things that blend in with the background, and unless it’s negative or a threat it won’t be obvious.
Review sites (or the news) have a lot more negative coverage than anyone bothering to mention all the good things, due to this same bias.
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