Question.Marketing

The YouTube Ads course

Module 5 - Keeping people engaged - retention is key

Engagement is the lever that decides what your YouTube ads cost, because Google actively measures how people respond to your content, and getting the engagement piece right should save you at least five to ten per cent of your ad spend.

Last updated 31 August 2026

Running time 6:57

What does this video cover?

  • 01Engagement has two sides: building the audience and getting the targeting right, and the content itself.
  • 02Video ads work like traditional PPC. The more clicks you get, the longer people stay and the more they act, the cheaper those ads become.
  • 03If your content does not serve the needs of the people who click, you get fewer impressions, your costs go up and you get ad fatigue.
  • 04Google Ads reporting shows whether people watch 25, 50, 75 or 100 per cent of your video, and low retention at the start is the thing to fix.
  • 05The spray and pray approach on max conversions can be a starting point, but you still have to think about engagement.
  • 06Getting engagement right should save you at least five to ten per cent of your ad spend, if not more.
  • 07TV ads are not working anywhere near as well on YouTube as real people or testimonials, because it is a different medium.
  • 08The best advert length we are seeing at the moment is between two and four minutes, which also gives you a bigger retargeting pool.

Full transcript

Why does engagement matter so much on YouTube?

Because it is crucial to everything you do with ads on YouTube, and not just the ads. It also decides whether the videos rank and gain organic traction.

We do not just want to concentrate on hooks. The content is going to be really important, but over and above that we want people to engage through the videos. There are two sides to this. There is the building of the audience and getting the targeting right, because if you get the targeting more focused you will get better engagement. And there is the ad itself.

If we think of video ads in the same way as traditional PPC, the more clicks you get, the longer people spend on your site and the more they take action, the cheaper those ads are. That is because Google is actively measuring how good you are. If the quality of the content you put out onto Google and YouTube is not brilliant, or at least does not serve the needs of the people who click on it, then you get fewer impressions, your costs go up, Google is not as inclined to show your ad, and you will get ad fatigue as you go forward.

All of these things you can fight against by having good engagement rates on your video.

What should you be looking at in the reporting?

Time on site and time on video, and the percentage watched. Within the reporting suite of Google Ads you can see how people watch through your ad, and whether they watch 25, 50, 75 or 100 per cent.

What we want to do is dial that in over time. What we do not want to see is really low retention rates at the start of the video.

Is the spray and pray approach ever acceptable?

Yes, as a starting point, but not as a strategy. I do see a lot of people use what I would call a spray and pray approach, where they put their ads out on max conversions, get as many views as they can and see where they go. You can use that as a starting point and grow and improve from there, and often that can be a good strategy, because you are teaching Google that you are doing a good job and improving.

But providing there are enough impressions available for the keywords and audiences you are trying to target, you need to think about engagement. Think about how engaging your ad is, and test different hooks at the start, different mid sections and different calls to action.

The worst thing you can do is run one video, one ad, one audience and hope for the best. Maybe your budget only allows you to do that to start with, but if that is the case, prepare another video. Maybe it is just the same video cut up in different ways, in different segments, with different calls to action and different ways of writing the description around that ad.

All of these things go into making your campaign a massive success, or into you having to learn, struggle, test, reiterate, produce more collateral and try different headlines to get that engagement up.

What is engagement actually worth?

If you get the engagement up, your costs come down, you get more impressions and your conversions eventually go up. Just through getting the engagement piece right, you should really be able to save yourself at least five to ten per cent of your ad spend, if not more, on top of the other things we teach in this course.

Should you run your TV ad on YouTube?

Not on its own, because it is a different medium. We have had several customers come to us with TV ads, and those TV ads are typically 30 seconds long. Obviously with TrueView, if you put an in-stream ad up as a TV ad and you hit the end of 30 seconds, you are going to pay anyway. You might as well have gone on for five or ten minutes, because you are not paying any more. It is not as if there is a taxi meter ticking once you go past that 30 second spot.

The other thing we are seeing with a lot of customers at the moment is that TV ads are really not working anywhere near as well as real people or testimonials on YouTube. We have got a couple of customers who have tried their TV ads on YouTube and, with our advice, added additional bits to them. They might take a 30 second ad and add another minute or two on the end: some customer testimonials, a bit more information about the product. It just does not seem to work as well using a TV ad on YouTube. It is a different medium.

So think about how you are going to hook people in, because Google is measuring how people react to the first few seconds of that video. Can you get them to stay, and do they stay for a long time?

How long should a YouTube ad be?

The best length of advert we are seeing at the moment is between two and four minutes. The longer you can get people to engage, through a four minute video for example, the more you can retarget the people who have watched a substantial part of it, because it is hosted on YouTube. Retargeting within this method does really, really well.

How do you know when your audience is wrong?

Test several audiences with the same ad and compare the retention. You will get clear winners. You might get an ad where 40 per cent of people are watching half of it, and the same ad with a different audience where only 20 per cent watch to halfway. That is a clear indication that your audience is not as good, or is too broad.

The engagement piece comes down to matching your keywords and your audiences so that you are not just putting the ad in front of everybody. You are putting it in front of the right people, who will stay.

So see if you can dial it in and get the engagement right, and I will see you in the next little lesson.

Where next?

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