usefulness,
utility the service (electric power or water or transportation) provided by a public utility; "the cost of utilities never decreases"; "all the utilities were lost after the hurricane"
quality an essential and distinguishing attribute of something or someone; "the quality of mercy is not strained"--Shakespeare
futility uselessness as a consequence of having no practical result
worthlessness having no qualities that would render it valuable or useful; "the drill sergeant's intent was to convince all the recruits of their worthlessness"
impracticality concerned with theoretical possibilities rather than actual use