Presumably, the contracts you conclude with your customers are perfected and tested. This is part of the craft of your sales management. Your procurement contracts will also be perfected and tested. That is part of the craft of your purchasing department.
But what happens when a customer makes a complaint to your company that was caused by input material. Are you sure you can “pass on” that complaint to your supplier? Have you systematically placed the clauses in your sales contracts next to the clauses in your purchasing contracts? Are the corresponding contracts designed “end-to-end”? It is worthwhile approaching lawyers who have been trained holistically to check all contracts for you to see whether they are well coordinated with each other. This is also part of a networked business approach.