Correct. ISO900x describes the process, not the product.
If your ISO900x manual says you make crap product and your process conforms to the description of the process then ISO900x is fine.
OTOH if you make an excellent product which meets and exceeds every spec imaginable but your process doesn't conform to the ISO900x documented procedures, you fail.
Do what you say, say what you do.
Been there. Done that. Tee-shirt is now my property :)
And usually costly.
PoP