Statistically, each business let it be banking, consumer goods, automobile and electronics are not able to give 100% performance. It may be fault of manufacturer, dealer, retailer or repair shop but yet it is not 100%.
Similarly eBay is not 100% proven (never will be) platform where both buyer and seller are covered. Based on your feedback (I see 9 right now), you have not spent enough time to understand and choose right sellers or statistically brought enough to make harsh comment like this.
It could be a specific transaction where you may have been lured by smart seller with attractive buy and thus got cheated. Thats happening around the world. So it is necessary to understand between a good deal with reputed seller or a very good deal with risk.
Please see if you have followed each step to resolve issue and then see what is end result. You have not said anything about why you made above statements. That should be said to assist you by other members and ebay support.