In general a nonconformance finding is assigned to the manager of the place where the NC was discovered. Very often a non-trivial finding has its cause in another department and its solution may lie in yet another department. The auditor usually has no idea of the originating or solution department. Some organizations assign an independent person to be responsible for leading a team of people for the investigation and solution. This is the method I have used for decades as I’ve found that assigning an NC to a single department leads to very shallow investigations and simple non-effective solutions like retraining or disciplining some random operator…or the NC just gets ignored.