carelessness vs nonachievement

carelessness and nonachievement both are nouns.

Word	Noun	Adjective	Verb	Adverb
carelessness	Yes	No	No	No
nonachievement	Yes	No	No	No

As nouns, nonachievement is a hypernym of carelessness; that is, nonachievement is a word with a broader meaning than carelessness:

carelessness: failure to act with the prudence that a reasonable person would exercise under the same circumstances
nonachievement: an act that does not achieve its intended goal

Other hypernyms of carelessness include nonaccomplishment.

carelessness (noun)	nonachievement (noun)
failure to act with the prudence that a reasonable person would exercise under the same circumstances	an act that does not achieve its intended goal
the quality of not being careful or taking pains