It seems like every supply chain college course acts like JIT is the greatest thing for manufacturing, but they always gloss over the negatives of it. The auto manufacturers make some really unfriendly contracts that basically put all of the onus on the supplier if the supplier has an issue and they end up paying for the down time.

Recent story of manufacturer located 2 miles from their customer assembling automobiles. Down time of 6 hours for the manufacturer costing $40M in fines due to their contract. https://www.reddit.com/r/antiwork/comments/t3qrxe/company_didnt_want_to_pay_me_a_fair_wage_and_the Explanation of how the contract meant they were fined so much: https://www.reddit.com/r/antiwork/comments/t3qrxe/comment/hyup3ou

It's really crazy how they can get suppliers to agree with this. But I guess the manufacturers are big enough to command it.