Literally anything that's out of the ordinary for a standard process.
It depends on the department what that means. Every department has its own list of exceptions.
It can be anything from an error code received by the ARTS, to packing needing to do adjustments because of overage shortage, to wrong DPCI in a location.
Usually if someone mention exceptions they're referring to IB clerical exceptions.
It could refer to errors on a purchase order meaning we may have received too much or too little from or even the wrong item completely from an outside vendor.
If you go to DC source and search exceptions it can give you some more specifics per department.