Earlier quoted context omitted.
> It doesn't matter if the traffic is 0% fake or 90% fake, all that matters is if the traffic is making you a profit or not. Only under the assumption that no competing, superior technologies exists. The worse the efficiency of the ad-model, the more attractive the alternatives will be. Criticizing Microsoft over delivering an inferior user experience twenty years ago is in the same category as the critique against G…
What alternatives? The key product here is Google search which is what attracts the consumers. The advertisers are dealing with Adwords not because Adwords is the greatest platform in history, but because Adwords is the platform where the consumers are. Ad fraud, no matter how massive, has no effect on the consumer side of Google search. Google has a strong incentive to fix this because any money going to scammers is…
This is a perfect summary of what is going on.
In this case I trust Google because their incentives are aligned with advertisers', and they certainly have both data (from Google Analytics and other sites) and means to distinguish between a human and a bot.