Fake Reviews from Competitor
Here is a classic case of Amazon's dubious policy.
A customer bought a product and gave damaging video review. In the same video he used another brand product for comparison. Further checking the profile of the reviewer - it was found that the reviewer had given positive review to the rival brand. Also the reviewer had given atleast 3 negative reviews within 5 days for another brand of the same category.
It was clear that the reviewer was fake and was working at the behest of another brand.
Seller support was informed and they accepted that the customer was suspect. However according to Amazon policy they cannot take down a fake review. According to them customer has to be convinced to take down the fake review, till then the seller should suffer.
When confronted the customer apologised through email. The copy was sent to amazon, yet the review stays active.