unsuitable vs unsuitability

unsuitable is not a noun while unsuitability is a noun.

Word	Noun	Adjective	Verb	Adverb
unsuitable	No	Yes	No	No
unsuitability	Yes	No	No	No

unsuitable (noun)	unsuitability (noun)
	the quality of having the wrong properties for a specific purpose

unsuitable (adjective)	unsuitability (adjective)
not conducive to good moral development
not worthy of being chosen (especially as a spouse)
not meant or adapted for a particular purpose
not capable of being applied