This article is so specious. I am actually shocked that something this bad would come out of a company that purports to understand internet marketing and analyt

This article is so specious. I am actually shocked that something this bad would come out of a company that purports to understand internet marketing and analytics. First, its comparing two completely different types of retargeting. It compares one campaign where Facebook retargeting makes up 3/4 of the impressions to one that is just general retargeting on the ad exchanges. These perform completely differently. Second, the timeframes are different. This makes a big difference especially if they have been running the same ads over a long period of time as ads (especially retargeted ads) tend to get ignored after a while so the falloff in performance can be quite rapid. Third, comparing post-click conversion across retargeting partners doesn't really make much sense. You're targeting the audience to begin with, you should probably care mostly what percentage of your audience they are reaching and what the CPM is more than the CPA. Unless these guys are doing fancy stuff (e.g. more aggressively retargeting people who have clicked but then did not convert) it actually does not make any sense that CPA would be any different at scale. Fourth, if you're running two different retargeting platforms on the same audience its possible that you're bidding up your own retargeting cost as the two platforms are bidding against each other. e.g. this shows a CTR of around 0.13% which is actually pretty good for FB retargeting, but they're paying ~$1 CPC which is really bad for FB retargeting.