The Unsayable: Why quality is hard to describe.

Quality is an interesting word for a lot of reasons. One of my favorite reasons it is of interest is that its own definition possesses the same slipperiness that the word attempts to allude to. The word is meant to be a generic category or things that are specific. One definitio reads "the standard of something as measured against other things of a similar kind; the degree of excellence of something." My brain reads that and goes..."huh" and also "I guess we use it that way, but can't a quality also be a bad thing...what about being excellent at being horrifying or something?" Quality is used as a metric and also to point to attributes that an item or person possesses. Consider the quality of an item?" This could mean that it is made well or that it is lightly used. Yet, we can also correctly ask what "qualities a person" has and no one would be confused. We can also discuss something else somewhat elusive using the word such as "leadership qualities."
The etomology doesn't really lead us way from this "Je ne sais quoi" place: "Middle English (in the senses ‘character, disposition’ and ‘particular property or feature’): from Old French qualite, from Latin qualitas (translating Greek poiotēs ), from qualis ‘of what kind, of such a kind’."
These definitions lead us very well into the strange slippery place that is wonderful for our exploratory discussion. To push us even further, if we talk about qualities as traits, attributes or properties, we can certainly use it for things that we can describe and define well, but "quality" is supposed to also point to those things which we cannot "put or finger on" or "clearly state"--this is the core of the idea behind the word "qualia."
As we explore what is a quality, I'd like to offer a few more ponderings to get the juices flowing:
What about "knowing,' "understanding", things 'clicking" or just that intuitive something that we pick up on, but have trouble naming or describing? Are qualities all existing as a degree? how strong it is, how clear it is? Are qualities and "qualia" all pointing to something we as humans perceive--even if that perception is somewhat intuitive?