This is just a little anecdote. Don't expect it to be deep or meaningful. I don't know, maybe there's something in here about feedback loops or focussing development effort in the right place, whatever.
Way back when, when I was just about fresh out of university and in my first programming job (1996), I got a bit of a reputation at being quite good at making our database and its applications go fast, including SQL query optimisation. This was using Ingres databases, hosted on VMS.
One day I was asked to investigate this particular stock report (I even remember the report id, “AGR48”, though I confess I have no idea now what the report was actually for). The report was too slow, I was told.
So I dug.
The report consisted essentially of a sequence of 8 giant SQL statements, each of which was quite slow. Lots of creation of temporary tables and the like. I think I rewrote the report and did make it faster, but that's not the point.
The point is: the report took about 4 hours; but due to a bug in the eighth and final SQL statement, the report output was always empty.
This report was effectively a four-hour no-op.
Unsurprisingly, the users didn't use that report.
Image credit: Steve Rhode CC-BY-NC-ND 2.0