It’s one of the great ironies in the debate over ad-blocking software, which heated up last week after Apple (AAPL) rolled out new ad-blocking features in its latest mobile operating system. And it begs the question: If the ads peppering our favorite sites were actually useful, would we still feel compelled to block them?

An article published Monday in WIRED examines the algorithms powering Facebook’s (FB) ad system, which the company says is designed to show users only the best possible ads. Essentially, the theory goes, if users see relevant ads where and when they’re actually relevant, users will be more likely to click on those ads.

The more natural and more relevant the experience, the more that users click, and the more that Facebook can charge. The virtuous circle is complete.

It’s a web advertising strategy that Google (GOOG) perfected. While there are lots reasons that Google eventually crushed Yahoo (YHOO) in search, Yahoo insiders are quick to point to Google’s algorithmic advertising auctions as a major factor. Rather than just giving ad space next to search results to the highest bidder, Google’s algorithms also factored in how likely users would be to click on them.

Better ads meant happier users and more clicks. Which of course meant more money for Google, and less money for Yahoo.

The challenge for most online advertising exchanges, however, is that they’re not Facebook or Google. They don’t run massive operations that generate their own content. They don’t know everything about what users want because of search queries and wall posts. And most importantly, third-party ad exchanges do not have the power to ensure their ads are displayed on these popular platforms.

For the past few years, though, the practice of optimizing real-time, targeted ad placement has been a major focus for big data practitioners. So-called data scientists have spent untold hours and written God-only-knows-how-many algorithms to try to improve ad relevance and get more people to click on them.

Whether these firms have been successful is open to debate. Typically, I still see untargeted ads for things I don’t want at all, or targeted ads for things I’ve already bought. Often, they make web pages slow to load, blare audio at me, or make me click to get them out of the way so I can actually read the article.

Hopefully publishers, along with the scores of data scientists putting their minds to the problem of advertising, will figure out a way to make ads a more natural experience across the entire web, not just on Facebook and Google. I can’t help but wonder whether the whole experience would be so bothersome to people—and, indeed, whether they’d actually click—if these ads were a little less annoying and a little more relevant.

To learn more about Facebook’s advertising business, watch this Fortune video:

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