Quality
Quality is fitness to use or we can say quality is perception, because all the people in this world will not have a same opinion about same thing, no matter how good that thing is in your point of view. If a thing is fullfilling my needs then I can say that it has quality but that might not be the instance for others as well because others may not like what I like! therefore we make perception about things knowingly or unknowingly.
For ex:- If I order something from the market that I need urgently but wasn't delivered to me at the right time that I can say that XYZ company is not providing quality service but for some other person if delivery time is not a concern then he will not critisize the company for the same reason.