Recent research by comScore indicates that just a fraction of campaign impressions reach their intended audience with the desired frequency, reports ClickZ.

Out of eight US brand campaigns with budgets between $400,000 and $2 million, not one reached more than 20% of their target with a frequency of four impressions or less.

And even those with over 4 impressions failed to hit the 40% mark for on-target delivery, comScore found.

The rest, which in some cases represented up to 80% of a campaign buy, were delivered either to the wrong segments in the US or to consumers outside the US.

There are many reasons for faulty ad operations: One is a basic lack of standards in ad operations. This is a problem that the Interactive Advertising Bureau and the American Association of Advertising Agencies (4As) are trying to fix, by developing a set of standards for use of insertion orders and other business documents.

Human error in insertion order is also common. Vertical ad network firm Adify, for instance, cited a recent insertion order in which an agency provided flawed ad tags for a client campaign — an error noticed almost immediately by Adify's ad operations staff.

But even after being notified, the agency didn't reply or fix the tag for two days. Adify staffers ultimately fixed the code themselves.

Ad networks often sub out a buy to other ad networks, setting the stage for even more miscommunication; a "fix," in this case, may not be passed effectively downstream to networks and publishers.

Many errors also stem from the sheer confusion of site and network  management. Agency staff have to be on top of all of their relationships — a daunting task at best.

To resolve rampant campaign discrepancies that arise from a flawed system, the 4As and the Association of National Advertisers (ANA) may have to step in. They are currently pushing an identification system for creative assets called Ad-ID, which may ease the process of ad placement and measurement in all channels. As an added benefit, it may improve online ad coding, said ad op firm Theorem.

Last August, comScore and began tracking ad networks' "potential reach" and "actual reach" for online-ad buyers and sellers, curbing networks' habit of exaggerating the number of publishers and pages they can place the ad.

In reality, major publishers reserve a small percentage of their ad space for networks, and it's usually the least valuable part, Valleywag explained.