This former executive just testified under oath that they change the auction rules without telling advertisers, and do so in ways that increase Google's revenue specifically in order to cook their quarterly SEC filing numbers and mislead investors into thinking the ad business is healthy.

The executive also testified that they've fallen far behind Meta and Amazon on ad campaign quality and revenue.

edit: The bottom of this article explains one of the mechanisms they use. The top bidder gets second place, and the second bidder gets top place. This increases their ad revenue on average (tricks like this get them 5-10%, they think they could take 15% because of their monopoly power):

https://www.msn.com/en-us/money/companies/google-tweaks-ad-a...

So... tl;dr: Their ad business is based on fraud built on top of other fraud.

He didn't even talk about the pop-under / youtube fraud that was reported a few months ago.

Each of the following guarantees YouTube makes to advertisers is demonstrably false:

- video ads will be displayed prominently

- video ads will be displayed on high-quality, reputable sites

- audio will be played back

- if the ad is over 5 seconds there will be a skip button that the user can click on, and the ad impression doesn't cost anything if the user skips it. (In many cases, the ads are rendered with an occluded or missing skip button.)

The difference between their claims and reality is responsible for a mid double-digit percentage of YouTube's revenue.