Simple data = simple personalization
Most personalized ads we see are based on the simplest of data; name, location, purchase history, browsing history and click history. This level of basic personalization usually leads to some pretty simple results; in fact, you only need to have experience with retargeting to realize that an ad featuring that washing machine you left in a shopping cart is now stalking you around the Internet.
This initial and also blunt approach was heralded as the beginning of personalization, but has not gone much further than this. There is a need for more data to be shared to move to truly personalized and relevant ads, and that is where we run into challenges.