I can think of a bad one where a significant number of laptops and 1st party docking stations were deployed. There was an issue where in certain scenarios plugging into the dock would brick the dock. It affected ~5% of the population in 90 days. Vendor response: fuck you.
One of the interns working on desktop support at the org figured out that certain laptop serial number ranges were affected. She then popped it open and found what turned out to be a counterfeit chip.
Flying monkeys were released and the CEO of the vendor got a call. End result: ~$40-50M redeployment of everything, eaten by the vendor. If they had been accountable from the beginning, they likely would have recalled $3-5M of devices and spent $300-500k on deployment.
On the flip, I remember one scenario where an off warranty device failed before its replacement was ready (and the replacement was another vendor). The part wasn’t available locally, and the account exec ditched a conference in Chicago, picked up the part from a depot in Indiana and drove it to Massachusetts overnight, with a CE waiting for it in the lot.