The Basics of Google Analytics Part 2
Welcome to today’s post on the second iteration of the Basics of Google Analytics. I’ve been hesitating to write this post since GA is such an expansive tool. It would take 20k words to go through everything that’s in GA.
So instead, I’m going to give you some pitfalls to watch out for and part 3 will be a high level overview. If you’re familiar with GA, you probably don’t need the overview. However, you should definitely still read the common definitions & pitfalls section.
Common Definitions & Pitfalls
You really have to understand the definitions and how Google Analytics works to really understand the underlying data. Data is useless without context and the context can’t be understood without understanding how the technology works.
This guide mostly deals with Universal Analytics and not GA4. GA4 is a whole other beast that while will be needed in the future, isn’t that intuitive or useful at the moment. You should definitely install it now to start collection data though.
Script & Cookie Blocking
This is infinitely annoying for me to have to explain to people for at least the 100th time IRL. No joke. I’ve had to point this out and explain it over 100 times to people that work in digital and to executives.
The Google Analytics tag is a JavaScript tag. For a variety of reasons, that tag doesn’t get fired and the user on your site isn’t tracked in GA.
Cookie Banner
The first problem that I’ll lump into this group is privacy banners. If a site asks you if they can place cookies on your browser and you say no, it’s not supposed to track that user.
This is highly dependent on whether the website loads the JS tag first, whether the website consider the tracker necessary instead of optional, your country’s laws on tracking technology (looking at you, EU), compliance of the website of said laws, etc.
Guess what happens when you give users the option of not being tracked and make it easy to do? They opt out of tracking at an astonishingly high rate.
Ad Blockers
This isn’t going to be a surprise for anybody that’s even a little technically savvy. Ad blockers don’t just block ads, most block tracking technology if it’s implemented on a large enough scale. GA is definitely implemented on a large enough scale.
If you’re curious, the EU has some of the highest ad blocker usage in the world. EU law also dictates that you’re not supposed to execute the script until they opt-in. Guess how often that happens.
Fortunately for website owners (unfortunately for privacy), GDPR is all bark and no bite, so most people execute the tags even without their consent.
If you’re forced to actually comply with GDPR, it’s exceedingly difficult to get good GA data on the continent.
Browser Blocking
I believe Brave is currently the only browser that blocks GA by default. Firefox, Safari and maybe others have options to block the GA script from running.
The point of me calling out the above 3 blocking methods means that you’re going to be missing data. 100 people actually show up to your website and you see and know about 90 of them. If you have 100 purchases, GA will show 90-95.
Without comparing your GA to something like a server logger and then filtering out bots, there’s no sure fire way to know what the real difference is.
By comparing purchases that don’t show up in analytics, the range of missing users I’ve seen in the US averages roughly 5%. Likely slightly higher for content sites since many ad blockers block purchases and causes users to turn them off to purchase.
In the EU, when you’re actually following GDPR, I’ve seen up to 90% missing data. If. You’re. Following. GDPR.
This is the problem GA4 is trying to solve.