One of the performance criterion a supplier of a packed product can refer to as the limit to further reduction of packaging material in a packaging system is "packaging manufacturing process".
In normal situations the supplier of the packaging must document this criterion. But is this criterion used the supplier must for practical reason have documentation filed in the records.
The reasons can be different and here are only given some examples:
Suppliers of packaging must be able to document these reasons in report and deliver such a report to the packer/filler. A short letter will not be enough because the user of the packaging (packer/filler) is responsible to authorities to be able to demonstrate optimal packaging. The packer/filler must also be critical to such documentation because in the end it is the packer/filler who will be legal responsible to the quality of the report.