Something appears to be malfunctioning and in kicks the NT. The nerve ends start to fray and the imperative to fight the real or imagined demon (you don’t know which it is at that point) takes you over body and soul. You investigate; you observe; you annotate; you fret; you think. That’s the important bit: you think. You weigh up all the possibilities and permutations until they are seemingly exhausted, finding reasons to justify your anxiety and reasons not to. And then you call in the expert. You place your dossier before him and ask: ‘Do I have reason to be concerned here, and, if so, what is the appropriate cause of action?’
And then the expert, realising that you’re a bright old thing who has already worked out more about the functioning and malfunctioning of the item in question than is generally known to the common herd, awards you the right to be made privy to arcane knowledge usually reserved for the cognoscenti. So then your mind settles, confident in the intelligence that either the demon is no more than a misty illusion, or that there is a means by which it can be destroyed. Hence the neurotic tendency gives you a head start in the lifelong learning stakes.
(And at the end of it all you die anyway and the whole process was probably pointless, but that’s another story.)