7 Incredibly Common Mistakes in Google Tag Manager

Let’s be honest, Google Tag Manager can be difficult to understand. I remember the first time I tried to set up GTM. I thought it would be like any other Google product I worked with in the past —straightforward and intuitive. Oh boy was I wrong!

In what became a cautionary tale, long before Portent days, I ended up inadvertently removing the client’s Google Analytics tag instead of adding tracking for form fills. Which, in turn, made it so that the site didn’t have any tracking for a week, since I could not figure out what I did wrong in GTM.

Looking back, I wish I had a guide to point out the most common mistakes beginners make when using Tag Manager and how to fix them. With a few years in the industry and plenty of experience with GTM under my belt, I decided to write a guide for marketers.

Keep reading to learn about the common mistakes people make when using GTM and how to fix them. I can personally guarantee it will save you a lot of headaches!

GA ID Not Set As A Variable

One common mistake I frequently see when I am doing a Google Tag Manager audit for a new client is that people forget to set their Google Analytics ID. One of the first things you should do when you are in the process of setting up GTM for your site is to create a custom variable for your Google Analytics ID.

Google Analytics ID Not Set as a Variable in Tag Manager

Configure the variable type as a Google Analytics Setting and just copy and paste your Google Analytics ID into the tracking ID field.

Naming of Tags and Triggers

When you use GTM, it’s imperative that you stay organized. If you don’t, you have a higher chance of making a major mistake. You may edit the wrong tag in the future or lose track of what your trigger was for and go so far as to accidentally delete it.

So when you create a new tag or trigger in GTM, you’ll want to ensure you are correctly naming your tags. The names of your tags should state exactly what the tag is.

Naming Tags and Triggers Effectively in GTM

From the above image, you can see that the tag for Bing is named “ Bings Ads – click to Call.” The first part of the label explains what platform that tag is for and the second part of the label is the action a user takes on the site that you want to track. If you ever get hit by a bus, the next person who goes in to edit your GTM tags will know exactly when you intended for them to do! (But seriously, don’t get hit by a bus.)

Not Using RegEx to Cut Down On The Number of Conditions Per Tag

One thing that I struggled with early on was creating a trigger or tag. I always had many different conditions that would cause the tag to fire. I frequently had more than four conditions on either a trigger or a tag and it would often break. Since I started working at Portent, I’ve learned that if you ever have more than three conditions, you should use a RegEx (or Regular Expression) to capture all the conditions you have in one statement.

Using Matches RegEx in Google Tag Manager

In the example above, matches RegEx was used to group more than 3 different potential values from a dropdown menu that someone could click within a website. This helped us track the dropdown event elegantly in GTM.

Not only will Regular Expressions simplify the number of statements in your trigger, but it will also help your tag manager container run faster, improving the speed of your site for users.

Not Creating Workspace When Testing Out Tracking

Let’s be honest, you have to frequently test GTM to determine the optimal way to track actions that a user is taking on your site. Whenever you make new changes to an existing container in GTM, you should do it in a new workspace.

Why You Should Create Workspaces in Google Tag Manager

The new workspace will allow you to make changes to the site and test out new tracking without jeopardizing your existing GTM setup or any other changes other users with access to the container are working on.Just remember, once you launch your container to make things live on the site, the workspace will disappear. Because of this, it’s best to save an older version of your main workspace before going live.

Underusing Folders

Organizing can be the worst. It’s never really fun to make things orderly, unless you’re that certain special kind of OCD. In the end, having things better organized makes things easy to find and improves work efficiency.

Using Folders for Organization in Google Tag Manager

If you have a large number of tags, it is highly recommended that you organize them into folders by tag type. This will help you identify the purpose behind groups of tags and keep track of analytics needs that are outdated allowing you to phase out tags you don’t need in the future and keep site performance up.

Not Annotating

One of the best feelings is when you have the right data tracking into your analytics, and you feel comfortable launching the changes you made live to the site.

Annotating in GTM for better results

Before you launch a container,make sure to annotate which version of your container you are pushing live. This is an excellent practice because you want to benchmark the changes you make. It’s also helpful for others to know what you updated in that current version of your container, in case there’s a problem on the site and you need to roll back

Events Come In As Not Set

One issue I regularly see when looking at our client’s event tracking, is that event labels are coming in as (not set) in the Google Analytics when looking at the event label report. The Event Label is an opportunity to pass in more information about where an Event Action took place.

Event Not Set in Google Tag Manager

Google recommends that you that you pass in {{Page Path}} variable in GTM into your Event Label field so you can determine where the events are taking place; labels are especially useful for things like call-to-action clicks that appear on multiples pages.

Where to From Here?

Hopefully this guide helped you determine solutions to some of the common mistakes that happen when working with GTM If you still have issues with your GTM setup on your site, feel free to reach out to us for help!

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  1. Thanks for the share.
    I always make the mistake to not annotate the versions of my tags.
    Like i know what i did, but when i will come back in a year it will be better to have some infos to remember. đŸ™‚

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