For more than half a century, publishers (TV, radio, print publications, etc.) have used "impressions" as the primary metric by which the cost for advertising has been measured. In an era of mass media, in which it was practically impossible to measure the number of true viewers, listeners, and readers, it was as close as they could get to measuring the (potential) impact of an advertiser's message. But in 2016, it is my belief that these publishers continue to use impressions, not because it is the best they can do to measure the effectiveness of their platforms, but because it is the most sure way for them to make money. Now I don't begrudge these businesses for making a profit. After all, that's presumably why they exist. But the biggest reason so many publishers are still charging for impressions is because advertisers, many of whom simply just don't know any better, are continuing to pay for impressions, even though there are better, more cost-effective ways.
A year ago, one of my teammates set up a conference call from a vendor that was developing a new impression-based advertising platform. I tried to be as kind-hearted as possible, but frankly told them that their days were numbered, and that I could not recommend their service to our clients... not because they had a lack of audience, but because they needed to provide a cost-per-action, or cost-per-conversion, or cost-per-lead alternative. Here we are a year later, and I'm frankly amazed that there are still so many advertisers out there that pay for impressions. I'd be a bit more understanding of it if there really was no other way, but publishers don't use these other superior methods, not because they can't figure out how to do it, but because they aren't being pressured to change.
I've previously commented on how you should ALWAYS direct ads to unique URLs so that you can more accurately track the effectiveness of your advertising (both the effectiveness of the publisher's platform, and the effectiveness of your creative). But there is no better way to ensure you are getting what you're paying for than to pay for performance. When we, as advertisers and advertising agencies, begin to properly leverage our position as purchasers of advertising space, we will finally start to see the kinds of changes in advertising that are long overdue.
If you'd like to explore how a platform like HubSpot can help you improve the effectiveness of your marketing efforts through improved, actionable metrics, and/or would like to explore how, with inbound marketing and content marketing, you can make better use of your marketing dollars than by throwing your money away on impressions, please let us know.