The problem is that bad reviews can be just as fake as good ones, as they could be written by the product's competitors.
Also, if a product is popular enough, odds are that even with a great product there'll be a small fraction of people who'll just happen to get a dud, while most of the rest will be satisfied.
Because of this, I tend to read both good and bad reviews, and give more weight to the longer reviews that go in to great detail about the product and why they rated it the way they did, with comparisons to other products being especially helpful. Also helpful are reviews by professionals who really know the field thoroughly. Unfortunately, such reviews are rare.
I also look at the ratio of good reviews to bad reviews, and look for products with many reviews, though on Amazon this strategy is not quite as effective these days as it once was. One of the big problems with Amazon's model is that it seems that most people buy the products shown on the first page or two of search results. Products on later pages might be just as good or even better, but they may never get bought or reviewed because they weren't on the first couple of pages.
It's become tedious fighting through the endless two word 5 star reviews, 1 star reviews because it was damaged in shipping and so on.
Add that Amazon are determined to show thirty no-name brands of cheap (and nasty) copies of whatever item you searched for, sometimes making the actual market leader really difficult to find, and it becomes more trouble than it's worth. I don't have hours to micro-manage and investigate every £10 purchase for fake product, fake review or not the brand I really wanted.
As a hugely keen early adopter of online shopping, these days I just go to the shops more and more often. It's just a shame there's so many fewer of them!
I love reading bad reviews on Steam, because they usually explain pretty well what the reviewer thinks is wrong with the game. I can then decide if that matters or not to me.
They stopped adding new content to the game? Maybe not too bad. It has a buggy always-online DRM? Deal-braker. Etc.
For me, it's the 4-star and 3-star reviews, and distribution of them compared to the rest (this can be gamed though). I see no reason that somebody would pay for 4 or 3 star reviews, and also competition would pay for 1 or 2 star ones instead. Primitive logic, but worked +-OK for me even on Amazon.
The chap on BBC radio yesterday said that he deliberately gave lower marks (4 star) than 5 because of exactly that - it looked too obvious.
He also said that some of the products that he was paid to review he didn't even use (hemorrhoid cream being one item).
I have also noticed the tit-for-tat reviews on Amazon between competitors. Its quite common on the cheaper products, in my experience. I've bought one or two awful things due to being caught by fake reviews, but I do tend to go back and leave a dreadful review.
I used to do the same, and still sometimes do for bigger investments like good headphones. Other than that i only use Amazon for things im knowledgeable about. For other things where I'm not sure about quality etc and i would have to rely on reviews to make an informed decision i usually don't bother anymore and source it from local brick and mortar stores, either go in person or use their online store.
Blows my mind how amazon is not paying more attention to this issue, i used to get almost everything on amazon - not so much anymore.
This happened to me once, I added my product to a sales channel and a competitor instantly gave it a fake review and lowest possible rating. I guess that was enough to keep people away, as that was the only review for several years.
Also, if a product is popular enough, odds are that even with a great product there'll be a small fraction of people who'll just happen to get a dud, while most of the rest will be satisfied.
Because of this, I tend to read both good and bad reviews, and give more weight to the longer reviews that go in to great detail about the product and why they rated it the way they did, with comparisons to other products being especially helpful. Also helpful are reviews by professionals who really know the field thoroughly. Unfortunately, such reviews are rare.
I also look at the ratio of good reviews to bad reviews, and look for products with many reviews, though on Amazon this strategy is not quite as effective these days as it once was. One of the big problems with Amazon's model is that it seems that most people buy the products shown on the first page or two of search results. Products on later pages might be just as good or even better, but they may never get bought or reviewed because they weren't on the first couple of pages.