Trust the overall numbers, not GA4 - a case study

Challenge:

The main problem we faced was the constant discrepancy between the GA4 data and the actual sales figures. This variance was not constant, which caused unpredictable situations when optimizing campaigns. For example, in one week the difference was around 10 %, while in the next week it was as high as 50 %.

Another problem was the evaluation of the META tool, which was severely underestimated by the attributional data-driven model in GA4. If we were to evaluate META campaigns based on the results from GA4, we would have to turn it off immediately.

Solution:

Instead of evaluating campaigns based on GA4, we decided to focus on tracking the overall trend using the metric overall PNO (cost to turnover ratio). This approach allowed us to monitor the development of campaign costs in relation to total sales (excluding VAT) and subsequently optimize them with regard to the real benefit of individual tools.

The next step was to adjust the investment ratio between hard PPC tools (Google Ads, Microsoft Ads, Sklik, ...) and META. We felt that META was not using its full potential and the data confirmed this.

One of the important added values of our agency is that we work with dozens of clients and can easily evaluate the best strategy for a given segment. That's why we decided to increase our investment in META campaigns even at the expense of PPC.

Implementation process:

1. 1. Monitoring overall PNO trendsA: We have implemented regular monitoring of this metric for all performance tools, including Google Ads, Meta and other platforms. This approach has given us insight into real ROI.
   2. Segmentation of PMAX campaigns on Google AdsA: To keep PPC campaign performance at a lower investment, we focused on Performance Max (PMAX) campaign segmentation. Through detailed segmentation, we achieved the same conversion rate while reducing the investment in PMAX campaigns by 24.8 %. Our conversions themselves increased by 17 %.

• Adjustment of investment in META campaignsA: Based on an analysis of the long-term trend of Meta campaign investments, we have reduced our PPC budget in favour of META campaigns. Since the client is experiencing a large ROPO effect, it is important for the client to track not only the conversions themselves but also:

• Interaction with posts and site traffic

• Brand awareness 

Results:

By segmenting PMAX campaigns and adjusting investments between PPC and Meta, we achieved the same cost 11% growth in annual turnover.

Conclusion:

This case shows that to effectively evaluate campaign performance, it's important to focus on overall real numbers and trends, not just GA4 data.