Symptom
Mobile conversion rate fell 18% and direct traffic grew to 38% of conversions — the signature of cross-device journey fragmentation in standard analytics.
Cause
Browser cookies are device-specific — when a user switches devices the analytics system creates a new anonymous visitor record and disconnects all prior touchpoints from the conversion event.
Impact
Discovery channels are systematically undercredited and closing channels overcredited — budget decisions from this data shift investment away from the channels that initiate journeys.