poorness vs deficiency

poorness and deficiency both are nouns.

Word	Noun	Adjective	Verb	Adverb
poorness	Yes	No	No	No
deficiency	Yes	No	No	No

As nouns, deficiency is a hypernym of poorness; that is, deficiency is a word with a broader meaning than poorness:

Other hypernyms of poorness include inadequacy, insufficiency.

poorness (noun)	deficiency (noun)
the quality of being poorly made or maintained	lack of an adequate quantity or number
less than adequate	the state of needing something that is absent or unavailable
the quality of being meager
the state of having little or no money and few or no material possessions