It’s an extraordinary number of accounts to ban, so either every second marketer on the planet is trying to promote something fraudulent, or bad sorts have been automating the creation of new accounts. According to Google, it is the latter: there are relatively few malicious players.
To ban 800,000 accounts, Google obviously needs automated systems:
One method we use to test the success of our efforts is to ask human raters to tell us how we’re doing. These human raters review a set of sites that are advertised on Google. We use a large set of sites in order to get an accurate statistical reading of our efforts. We also weight the sites in our statistical sample based on the number of times a particular site was displayed so that if a particular site is shown more often, it’s more likely to be in our sample set. By using human raters, we can calibrate our automated systems and ensure that we’re improving our efforts over time.
I wonder if Google has estimates on how many automated bans were made in error? Their previous post also goes into great detail at how they find the bad guys, but so far there is no mention of how they fix their mistakes. Wrongfully banned Adwords users will point out the speaking to a real person to get the suspension reviewed can be very difficult.
It has been suggested that the mistakes are simply collateral damage and bad luck to those who lose their accounts. Unfortunately those most likely to be affected are those who rely on Adwords for their business. And Google has a monopoly in many countries.