Some business users have been chasing me all week to produce a report using some old report with some modifications.

I didn't write the old code and have no context as to what the data is.

My current reaction is:
so you want a report that says X using some vague input which you haven't clearly defined or explained to me...

Have you heard about black boxes and overfitting (i.e. reverse engineering a process based on sample data)?

TLDR: I can generate a report that will say anything you want it to say... doesn't mean it will be right in future use cases.

Why don't people (originally GBoard suggested peepee) understand "junk in = junk out"