Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Extremely poor quality!

I would give this item 4 or even 5 stars if it works. It's really helpful and comfortable when it works. Unfortunately, it failed just after I used this cushion about 12-15 times for less then 1 month. BTW, this is my third purchase - initially two years ago I bought two cushions for my wife and me and after 2 seasons and the very lightly usage one of them stopped working. Assuming it's just bad luck or occasion, I ordered one more - and will never buy again. 67% failure rate looks too much. Now it's too late for the return and anyway I'd have to pay shipping fee. Shameful quality and waste of money ... Do not buy it!