incompetent vs ineffective

incompetent is a noun but ineffective is not a noun.

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

incompetent (noun)	ineffective (noun)
someone who is not competent to take effective action

incompetent (adjective)	ineffective (adjective)
not qualified or suited for a purpose	not producing an intended effect
legally not qualified or sufficient	lacking in power or forcefulness
not doing a good job	lacking the ability or skill to perform effectively; inadequate
not meeting requirements
showing lack of skill or aptitude