Heh, so true in many cases. I had rewritten a utility that scanned a directory and moved files to s3 from Perl to Go and eventually a different team took over the code. A bug popped up and they were not confident to update the "legacy code." I could do not but chuckle to myself: this was like a fee hundred lines of well organized and fully unit and integration testable code with a readme and runbook and grafana/prometheus and structured logs aggregated in Splunk. And that has been running for like 2 years. They just didn't want to even attempt the fix and in fact pushed it off indefinitely.