“Twenty years after last using the software, I still remembered the installation procedure”
A German tax audit needed documents off backup disks nobody could read. The American company that had bought his old employer had no one left who knew the software, so they called a retired man and paid him a day rate worth about a month of his pension. Then the auditors found duplicate 2013 invoices and started saying large-scale tax fraud. It was one year of archives imported twice, and he found it in a day. Every organization runs something like this and none of them budget for the person who remembers it.