Google perpetuated massive AdSense fraud, where they pretended that both competition was bidding up on search terms and actual people (and not bots) clicking ads to siphon advertising money away from traditional media. During 2015 or so I was running Google search ads for a niche of a niche business, there was nobody else running advertising on my search terms, yet Google would rather not show any ads then allow me to run them for less than $2.5/click. Because of low visitors, I could see with high degree of certainty that clicks that I'd get, despite selecting "first part search only" were all bots. Was a waste of money even at 500$/mo budget, even when legitimate leads would be worth to us easily couple hundred.