A stupid story.
I was taking my annual vacation a month ago. We were building a custom app for payroll because the law works differently in my country. We had the scripts on our laptops, but there were some records and templates that are only on the sandbox.
I went on vacation imagining that the worst thing won't happen, but it did. The client had some problems with NS, so my team thought they will cancel the subscription of the sandbox only, so they moved everything to production. But the client actually canceled everything with NS and decided to buy a different system, and both accounts got closed. And now we have to redo that part again.