When you set up an ad on Facebook (and many other ad services), you can define a "conversion" (I'm more familiar with how google calls them, I'm not sure if tha

When you set up an ad on Facebook (and many other ad services), you can define a "conversion" (I'm more familiar with how google calls them, I'm not sure if that's what facebook calls it.). You can read about it here: https://support.google.com/google-ads/answer/1722022 https://support.google.com/google-ads/answer/1722022. Then, you can set a target "Cost Per Action", which factors into your bids and therefore how much you spend on advertising and where you advertise. That's why if you're doing ad fraud, you'd want to take it all the way through to whichever action "counts".