Google recently revealed that their click fraud is less than 0.02 per cent so it is barely a problem anymore. This means that for every ten thousand CPC, less than two are possible click frauds. Moreover, Google has algorithms that automatically compensate adwords users based on the percentage click fraud.

Ads pay for Google's multibillion dollar business. They are introducing Pay-Per-Action in order to diversify their income channels, not because Adwords is failing.