I genuinely loathe the over-familiar vibe you get from targeted ads in such a way where no matter how relevant to me the given product is, if you advertise it like that, I'm immediately suspicious of your intentions. If I'm talking about longboards a lot around my house and get ads for longboards, I would go so far as to say I would go out of my way to not buy any of the brands shown to me.
I think this is an underrated metric in terms of how advertisers are organizing their spend; the creep factor. If your first impression with a potential customer is creeping them out, how are the odds of them giving you a sale?
I have a similar annoyance: the obvious ways marketeers try to get me in their funnel (I call it conversion aversion). It's hard to measure, so it's not taken into account by marketeers, but I'm quite certain the amount of people annoyed by conversion optimization tactics represent a lot of potentially lost sales.
I think this is an underrated metric in terms of how advertisers are organizing their spend; the creep factor. If your first impression with a potential customer is creeping them out, how are the odds of them giving you a sale?
Just my 0.02.