Google Analytics being the gold standard for reporting on website traffic and engagement and Pardot identifying which prospects are taking action on your site, putting these together just makes sense. As much as you can get reporting out of Pardot, using the Google Analytics Pardot integration gives you more data collection about how people are first finding your site.
The Google Analytics Pardot integration pulls UTM parameters into Pardot, where they can sync with Salesforce. Pardot collects data from five Google Analytics tags: campaign name, medium, source, content, and term. This connector simplifies the flow of Google Analytics data between Pardot and Salesforce.