Now, trading desks and media buyers may well point out that they are adept at not charging for unviewable ads -- I've had mixed reactions on whether this is the case. However, the point that many advertisers would raise is that because display is about awareness, the most important aspect for any brand is that its campaign is seen. It's all well and good to get some advertising credit returned after a campaign has run for ads that were not seen, but brands would far rather see their budget turned into eyeballs when the campaign is active so it stands the biggest chance of success.
Back to Meetrics' figures -- and to be honest, the main reasons why ads are ruled unviewable are not a huge surprise. However, it is very refreshing to see a metrics company offer reasons and to let advertisers and agencies see what those main reasons are. If I had hazarded a guess before seeing the figures, I'd have presumed that appearing below the fold or in inactive tabs would have been the main culprit. However, in the case Meetrics cites, with the proviso that this can change from one campaign to another, 14.5% of ads are deemed unviewable because they have not been displayed for long enough. Considering that means they have been in the frame for less than a second, there must be some very fast scrollers out there.
So 14.5% of ads are not shown for long enough, then we have 12.5% are displayed below the fold with 10% not having sufficient pixels (rules only call for 50% of an ad to be viewable) and 6% being served to inactive tabs. In the case of this campaign, then, the order of why ads were unviewable is that nearly half of the Web's ads are unviewable was because they are were shown for the full second, were not in the frame, did not have more than half of their pixels viewable or were in a tab that's not open.
As I say, the reasons are not unexpected, although revealing the relative percentages is a useful insight. It does little to help an advertisers who was hoping to reach its core audience, although it does at least give a reason and shows that the unviewable adverts have been noted and accounted for, rather than thrown under a heading of ads that weren't in a position to be seen. Results will vary from one campaign to another but as a glimpse in to the issue why ads are not seen, Meetrics' figures are well worth a look.