How a spreadsheet quietly becomes the system
It starts as a one-off report. Then someone else needs it too, so it gets emailed around. Then it's the thing three people edit and one person has to reconcile every week. By the time anyone asks whether it should still be a spreadsheet, it's already the actual system of record — with no login, no version history that matters, and no way to tell who changed what.
What spreadsheet automation actually replaces
Usually one of two things: the compilation (pulling numbers from several sources into one sheet every day or week, by hand) or the reporting (turning that sheet into something someone reads, on a schedule). Both are mechanical, both are exactly the kind of task that breaks quietly when the person who maintains it is away.
What this looks like when it's real
The internal data-entry tools case study is exactly this pattern — a shared spreadsheet job-tracking process replaced with a real login-gated tool and an actual closeout state. Where the source data starts life as paperwork rather than a spreadsheet, the PDF/OCR extraction pipeline covers that end of the same problem.