(Going back over a decade) I guessed Google was under-monetizing, and then they could just keep slowly turned the knob, and the indicator was when they couldn't turn that monetization knob any more.
Google's Ad platform is at this point now. It has turned in to this jumble of UI anti-patterns and dark patterns. Each successive rollout of a new feature is basically, add more text we can test and relinquish your bidding control to us. At a slow, incremental pace this works. Eventually, however, they max out either what the advertiser can budget, or remove enough of the advertiser's ROI that it doesn't work any more. Then the risk becomes, rather than failing to grow revenue, that they actually collapse it.
One of the things that stuck with me the most, was many years ago Yahoo would go in and change the text of your search. That was egregious on many levels. The non-self service display ad networks would make you jump through a bunch of hoops to run a campaign and then make it as hard as possible to stop the campaign without it being fraud. Adwords, on the other hand had none of these problems. It worked fantastically. Not anymore.
Google's Ad platform is at this point now. It has turned in to this jumble of UI anti-patterns and dark patterns. Each successive rollout of a new feature is basically, add more text we can test and relinquish your bidding control to us. At a slow, incremental pace this works. Eventually, however, they max out either what the advertiser can budget, or remove enough of the advertiser's ROI that it doesn't work any more. Then the risk becomes, rather than failing to grow revenue, that they actually collapse it.
One of the things that stuck with me the most, was many years ago Yahoo would go in and change the text of your search. That was egregious on many levels. The non-self service display ad networks would make you jump through a bunch of hoops to run a campaign and then make it as hard as possible to stop the campaign without it being fraud. Adwords, on the other hand had none of these problems. It worked fantastically. Not anymore.