A nonconformance is a non-fulfilment of a requirement. <snip>
Precisely. And as I said, requirement(s) have to be defined, with specificity, somewhere in an organizations documentation (which could include customer requirements, product parameters such as dimensions, colour, surface finish, requirements in applicable regulations, etc.) or other places (e.g.: blueprints or local, regional, federal, national or international regulations).
And if you take ISO 9001 alone, as general as it is, the standard its self is nothing more than a list of requirements, and this is probably why you're thinking as you are, the absence (or failure) of which in a company in a compliance to the standard audit results in a nonconformance input. And while ISO 9001 does not state who is responsible for a specific clause in the standard (and typically is a number of different people in various positions).
E.g.: You have a print with a dimension of x inches =/- .01 inch - That requirement defines what is nonconforming (which is a measurement outside of that range).
As I have been saying, you have to define what, specifically, is a nonconformance to begin with. You do this using all the various requirements, regulations, etc. None the less, all the requirements have to be defined, and they define what can be inputs to the nonconformance system.
There is one essential input to the nonconformance process: the (perceived) nonconformance itself (such as, "out of tolerance dimension on part"). I do not see value in writing this in the QMS, as it seems very obvious and not helpful
Well, it's not "one essential input" - Again that is a general statement - there can be hundreds of requirements. Even if a company does (for example) state somewhere that not meeting a requirement requires a nonconformance to be input, it's only one sentence.
In some ways we're saying the same thing. I just see more nuance than you have been expressing - probably because I see a nonconformance
system to be a very broad system which is not confined, for example, to products.
Another way to get where I'm coming from: You make a part. You define requirements on a print. By doing that you are defining what will be inputs to the nonconformance system (anything which doesn't meet the requirement(s)). Let's say you define 100 dimensions on a print. That's 100 different potential inputs (each is a specific requirement) to the nonconformance system.