incompetent vs bungler

incompetent and bungler both are nouns.

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

As nouns, bungler is a hyponym of incompetent; that is, bungler is a word with a more specific, narrower meaning than incompetent:

Other hyponyms of incompetent include blunderer, botcher, bumbler, butcher, fuckup, fumbler, sad sack, stumbler, slouch.

incompetent (noun)	bungler (noun)
someone who is not competent to take effective action	someone who makes mistakes because of incompetence

incompetent (adjective)	bungler (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