Ads managers show dozens of metrics, most of which are decoration. Knowing which few matter — and how long to wait before believing any of them — is most of the discipline.
The metrics that matter
- Cost per acquisition, against the number you decided in advance.
- Return on ad spend, for ecommerce, calculated on gross profit rather than revenue.
- Blended CAC, from your own books. The honest one.
- Frequency, as an early warning of fatigue.
- Hook rate (three-second views over impressions), to judge creative openings.
The vanity metrics
Impressions, reach, clicks, likes, and cost per click tell you almost nothing about money. Cheap clicks that never buy are the most common way people convince themselves a losing campaign is working.
Give it time, then judge fairly
Judging after two days is judging noise. Most decisions need at least a week, and enough conversions to be meaningful — a handful of purchases is not a verdict on anything.
If your volume is genuinely low, accept that you are making decisions on thin evidence and prefer bigger, longer tests over many small ones.
Watch the trend, not the day
Daily costs swing wildly for reasons that have nothing to do with your ad. Look at seven-day rolling numbers and ask whether the direction is right, rather than reacting to yesterday.
Try it
Strip your reporting view down to five columns: spend, conversions, cost per acquisition, ROAS, frequency. Delete everything else, and check it weekly rather than daily.