Anecdotally, I have a generally negative perception of the brands placed in the way of actual search results. They're rarely relevant to my actual wants or needs, let alone the search terms, and it colors my expectations that they'd be capable of helping me even if I did want their products or services given the low QC on where their ads are shown.

Advertisers lose because they're only paying to try to snipe each other's customers when directly searching for brand names. They could pay to advertise on the more generic search phrases, but it's more likely to convert a user into a sale if they're ready to buy something and googling a competitor's company name to go to their website.

For users just looking for general information, the company paid for an ad that was less likely to convert to a sale. And it fucks their analytics, too, since there's no indication to them that users didn't even search for the key term they're paying to advertise with.