The protocol for when traffic drops 30% overnight

The protocol for when traffic drops 30% overnight

A media site's traffic cratered 30% on a Tuesday. Panic. Half the room blamed Google, the other half blamed a redesign. Nobody had a method, so they had a fight.

The anomaly protocol:
— First, segment by source to see if the drop is one channel or all of them
— If one channel, the cause is external; if all, suspect your own tracking
— Check whether the GA4 tag still fires on every key template
— Compare to a non-GA source like server logs to confirm it's real
— Only then look at algorithm updates or seasonality

The drop hit every channel equally, the tell-tale sign of a tracking break, not a traffic loss. A deploy had dropped the GA4 snippet from the article template. Server logs showed traffic was flat.

Real traffic never moved. They re-added the tag and the "drop" reversed in an hour.

Lesson: an all-channel drop is almost always your tracking. A one-channel drop is almost always the world. Segment first, panic never.