If there is one universal truth about tracking things on the internet, it’s that data is never as clean as you might expect. And vendors make a ton of money helping advertisers and publishers try to get clearer on that data. Just Google “Ad click fraud” or “Click fraud” and you’ll see half a dozen different companies “saying goodbye to click fraud.”
And the sad reality is, the same is true in email. While I won’t classify it as fraud, the data is dirtier than we might first think.