Every Friday, someone exports three CSVs and spends four hours making the numbers agree. They never agree.
Meta and Google answer questions about their own contribution using different attribution rules. Decide what your scoreboard is.
Platform ROAS is a bidding signal, not a P&L
Use platform numbers for within-channel choices. Use blended measures for total-spend and business decisions. Do not sum channel ROAS into a company number.
What each interface is actually good for
Meta is best for judging creative. Google is best for judging products and assets. Your commerce platform is the place that knows what you actually sold.
A lean weekly scoreboard
- Total ad spend
- Total revenue
- Blended MER
- New customer revenue or count
- One directional efficiency number per channel
If the same manual export happens every week to produce the same numbers, it is not analysis. It is a scheduled job a person is executing by hand.