Nail / head I think; if advertising was truly optimized for what a potential customer is interested in and might buy, there would barely be any ads.

But that's the "buy this now" type of ads, another big category that I don't see on the internet much (...because I have an ad blocker but that aside) is the "brand recognition" type - Nike and Coca Cola for example, a lot of their ads are passive in that they just want you to see the logo and become familiar and comfortable with it. Product placement in media.