Last time we talked about the “Mystery Metric” we’re seeing drive the cost of YouTube ad traffic:

To recap:

👇When our “Mystery Metric” goes DOWN, cost of traffic goes UP ☝️

And vice versa:

☝️When our “Mystery Metric” goes UP, cost of traffic goes DOWN 👇

We asked you what you thought it could be.

And there were some great guesses, like…

  • “View Rate!”
  • “View-through rate?”
  • “Relative CTR?”
  • “Click thru rate?”
  • “Cost per click?”
  • “Watch time.”
  • “Just tell us :-)”

So what is this "Mystery Metric?"

Let’s look at Google’s explanation on how we’re billed for Video campaigns where we are bidding on conversions:

“Google Ads smart bidding products automatically set bids to achieve the objective of the bidding strategy. In the case of Video ads like Video action we attribute conversions to engagements, which are defined as clicks on the ad or 10 seconds of viewing time. As a result, when optimizing for conversions we cannot bill on clicks because conversions are also attributed to users who have watched at least 10 seconds without skipping. Therefore, we automatically set the effective CPM bid based on a prediction of given impression's likelihood to convert, defined by the attribution requirements above.”

Ok, let’s break this apart a bit:

  • Conversions are attributed to “Engagements”
  • “Engagements” are defined as 10 seconds of view time or clicks on the ad
  • We are billed on a CPM basis (CPM = cost per 1000 impressions)  for Smart Bidding campaigns (Target CPA, Maximize Conversions, Target ROAS, Maximize Conversion Value, etc.)

Key Point: Our traffic cost is based on Google’s prediction of how likely an impression is to generate a conversion.

Ok - so with all this in mind, back to our “Mystery Metric”...

If Google decides how much we pay per impression by predicting how likely one of our impressions will become a conversion...

...What’s an “early indicator” that an impression will become a conversion?

(Hint: look again at the excerpt above on how  ow Google attributes conversions ^^)

That’s right:

Between an impression and a conversion, lies our “Mystery Metric”:


Impression → Engagement → Conversion

(Congrats to Nicolai Grut, Martin Levi & Scott Pringle who all sent in the correct answer!)

So what does this mean for:

❓How you should structure your YouTube ads?
❓How you should set up your funnel?
❓How you should optimize your YouTube ad campaigns?

Comment below and let us know your thoughts!

(PS - this intel from Google + our engagement / traffic cost data suggests some interesting possibilities regarding how exactly Google charges for traffic… Any insights on that?)

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What are your YouTube ad questions?

In the meantime though, what questions do YOU have about YouTube ads?

Let us know in the Comments section below, and we’ll make sure to cover your question in an upcoming post.

Have a great week!

The VidTao Team

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