incompetency vs incompetent

incompetency and incompetent both are nouns.

Word	Noun	Adjective	Verb	Adverb
incompetency	Yes	No	No	No
incompetent	Yes	Yes	No	No

incompetency (noun)	incompetent (noun)
lack of physical or intellectual ability or qualifications	someone who is not competent to take effective action

incompetency (adjective)	incompetent (adjective)
	not qualified or suited for a purpose
	legally not qualified or sufficient
	not doing a good job
	not meeting requirements
	showing lack of skill or aptitude