Journal · March 2026

Why event names rot

The first tracking plan in a young company is almost always honest. The third is a museum. The fifth is a hazard.

Event names rot for a boring reason: product language moves faster than instrumentation. A screen called Home becomes Today, then For You, then a tab that is not a screen at all. The event `Home_Viewed` remains, because deleting it feels like burning evidence. Analysts keep it “for history.” History, in App Analytics, is usually a duplicate fire on a route that no longer exists.

The second cause is politeness. A growth lead asks for `PromoBanner_Shown` for a fortnight. The banner dies. The event does not. Nobody wants to be the person who removed the series the board once liked. In Cohort Instrumentation we treat this as a governance failure, not a tooling one. Every event in the house standard needs a retirement rule: last useful date, owner, and what chart must be rewritten when it goes.

A third rot is versioning in the name. `Checkout_v2_Started` tells you that someone was afraid. Versions belong in a changelog, not in the verb. When v3 ships, v2 becomes a zombie that still fires from a cached Android build. Your funnel now contains time travel.

We ask teams to inventory last-fired timestamps before they discuss north stars. If an event has not fired in thirty days and is not a legally required audit trail, it is a candidate for the graveyard. The graveyard is a documented list, not a silent delete. Silent deletes create the folklore that “analytics broke in April.”

Names that describe intent survive redesigns: `LessonCompleted`, `RideRequested`, `PaymentFailed`. Names that describe furniture do not. If you can point at a pixel, you probably named the pixel. App Analytics is not interior design.

Read next: Instrumentation debt in mobile apps, or return to the journal index.