On the website, we use Plausible to measure traffic. It is a kind of light version of Google Analytics, but which is completely without cookies, and gets all traffic with it.
It also includes UTM tagging that is placed on the ads so that we can track how many people create accounts via the ads.
When we compare the figures of Meta Business Manager and Plausible, we see that Business Manager only registers 53% of the actual conversions.
If we hadn't had Plausible, we might have stopped advertising on Facebook and Instagram, as we thought the cost per acquisition (CPA) was too high.
But in reality the ads work very well and the cost for someone to create a new account on HurryUp is only half of what we thought.
Recommended reading: Why Plausible may be a better alternative to Google Analytics.