I'm befuddled why Amazon, who has been in this game the (second?) longest and has had the most opportunity to take advantage of deep learning can be so bad at d

I'm befuddled why Amazon, who has been in this game the (second?) longest and has had the most opportunity to take advantage of deep learning can be so bad at delivering relevant advertising. I suspect there's some institutional inertia that prevents them from deploying better technology. Another example is that Amazon is incapable of recognizing the difference between something bought as a gift versus something for yourself. Thanks to one Christmas present 10 years ago I still get recommended Playstation games.