>If nobody who came from those links bought anything then the ad spenders would stop buying ads from them Who has the ability to find out if those paid links a

>If nobody who came from those links bought anything then the ad spenders would stop buying ads from them Who has the ability to find out if those paid links are the reason customers bought things? Google will tell you that every single person who clicks a link and then buys something bought said thing because they clicked your link (please pay google now). But if I sold a lot of product while running web ads, that doesn't necessarily mean that every web ad purchase is something that wouldn't have existed without the web ad. You COULD spend effort figuring out how much your ads actually impacted things... but see the reply above. The point is, I think everyone involved in this equation is discouraged from actually finding out how effective the ads truly are, which can lead to inflated numbers. In fact, Google doesn't even have to report accurate numbers at all, as long as they are feasible. I don't think they are doing this obviously, but it's something to think about.