Lessons from Automating an Accounting Workflow Nobody Touched for 10 Years
When a process has survived unchanged for a decade, there's usually a reason. Navigating the politics and technical debt of replacing it taught me more about change management than any course.
The accounting journal-entry workflow I automated had lasted because it worked well enough, lived in files people already knew, and failing it in public would have been worse than wasting a morning. A Canadian firm was copying SAP exports through seven manual steps across three workbooks. Errors showed up in audit review, often weeks later. The technical job was a Power Query pipeline that refreshes in 12 minutes. The real job was not scaring the people who owned the close.
I shadowed the team for two sessions before writing a query. Every formula, every mapping table, every "we always paste it here" was load-bearing social knowledge. Replacing seven copy-paste steps with Refresh All only shipped because the output format did not change and a validation query turned green only when debits equaled credits to the penny. The first month that check caught three mismatches that used to wait for audit.
Non-technical staff ran it after a 20-minute walkthrough. A one-page guide and a one-button VBA wrapper mattered more than a clever M pattern. Maintainability sat in a lookup table for account mapping, not in hunting through formulas. That is the opposite of a rewrite-for-rewrite's-sake: keep the ritual, remove the risk.
A process that survives a decade is rarely just lazy. It is a coalition of habit, fear, and a format the next person in the chain already expects. Automating it is change management with an ETL costume. If the numbers still land in the same cells, people will let you take the paste buffer away.