(...) So, this is basically why any professional reviewer won't do a negative review. To do it ethically, one would need to test across many systems with different test subjects who can't induce bias in one another by describing to each other what they are hearing, and it's simply easier to return the gear and say, "Sorry, I wasn't able to get this to work properly in my system". Some years ago I had a different opinion, but sending cables to hundreds of people to test has given me a slightly different perspective.
I have reported this before, it is a an old story, but I will repeat it again. A well know high-end magazine from Hong Kong - sorry I do not remember the name anymore, they had great photos and an extraordinary graphical quality - once explained their review policy in an article. The editor got the equipment to be tested and send it to a reviewer he felt that could do a proper review. If the reviewer disliked it, he would follow it to his next choice and this process would go on until some reviewer liked it and wrote the review. If no one (their had about 10 reviewers) liked the equipment it was simply returned to the manufacturer with a letter thanking him for making it available and apologizing that none of the reviewers had a system or knowledge that could do the honors to his equipment.