A quick analogy to explain quality
After Cesar’s comments on You shall not compromise quality! and the obvious confusion between quality and qualities, I created the following simple analogy. I believe it conveys the point efficiently.
If your house is flooded, two plastic bags and some tape will be enough to keep your feet dry. The quality requirement (qualities) is that they do not have holes. The quality of the bag is measured by the number and position of the holes. If you are lucky they are all high on the bag and your feet may stay dry.
If you go fishing in a swamp, you should use specially designed boots. The quality requirements (qualities) are that they have no holes, are able to resist various environmental aggressions and that they are comfortable. The quality of the boots will be a combination of the comfort, sturdiness and water tightness.
Compromising quality is that you don’t apply the best practices, use the wrong tools (ever tried to knit boots or plastic bags ?), promising more than can be achieved (like trying to make a plastic bag with half the necessary plastic or making boots when the soles are above budget).
Final point, good boots are not cheap. Plastic bags are relatively cheap and can be used for lots of things but they easily break and end up polluting the landscape (who just thought Excel out loud ?!?).