I would say its because many people think of quality in terms of a desirable thing. When the thing is not desirable its not quality to them anymore.
If I see a handcrafted quality made carpet and I hate it. Its still a piece of junk for me. A well made piece of junk admittedly. I can appreciate the thousands of hours people put in making the carpet but many people equate the term Quality to "good product" a product you don`t enjoy is not good anymore.