The first product manager names signup_complete as if the phrase were granite. The second inherits a half-finished onboarding and adds SignupSuccess because the console search is case-blind and the ticket was due Friday. The third, arriving after a reorganisation, ships user_registered to “align with the data team.” Three years later, activation is a choir of near-synonyms, each with a different idea of what counts as finished.
Decay is not malice. It is what happens when a catalogue has no grammar and no funeral rite. In the Event Taxonomy Atelier we treat this as an editorial problem. A name is a claim. If two claims occupy the same moment in the app, history is already lying.
The smell of a dialect
You can hear decay in the prefixes. User, App, and New appear when nobody wants to own the noun. You can see it in tense: a mix of past participles and present clicks. You can measure it when a dashboard needs a footnote longer than the chart.
A practical test we use in studio: ask three people, separately, to write one sentence defining the event. If the sentences do not share an object and a completion condition, the name has already split.
Funerals, not silent overwrites
Teams often “fix” decay by renaming in place. The old meaning remains in last year’s board pack, now attached to a new payload. Dual-write for a dated window, then stop. Put the stop date in the property dictionary and in the engineering ticket. If you cannot name the date, you are not ready to rename.
The third product manager is not the villain. The missing council is. Week five of the atelier exists because a wiki page cannot reject a hack-day event at 4pm. Someone has to say no in a log that survives Slack’s retention policy.
If your catalogue already has three names for the same moment, pick the dullest one, document the other two as aliases with an end date, and resist the urge to invent a fourth that is “more semantic.” Semantics without a funeral is how dialects start.