Switching 7-day-click to 1-day-click attribution drops reported ROAS ~22% but cuts true CPA error in half

Switching 7-day-click to 1-day-click attribution drops reported ROAS ~22% but cuts true CPA error in half

CPA = cost per acquisition. Attribution window = how long after a click a sale still counts.

Window comparison vs geo-lift truth, 19 accounts:
— 7d-click reported ROAS: median 3.1x
— 1d-click reported ROAS: median 2.4x ▼
— But 1d-click sat within 11% of incremental truth; 7d-click overstated by 27%
— Long sales cycles (>$200 AOV) are the exception — keep 7d there

The prettier number is usually the more wrong one.

Read: optimize impulse-buy accounts on 1-day-click; you trade vanity ROAS for honest CPA.