I'm no expert in this area. But I think this is due to the inherent nature of a system where the ads are all pushed by people marketing specific products, rathe

I'm no expert in this area. But I think this is due to the inherent nature of a system where the ads are all pushed by people marketing specific products, rather than a centralized "what is the best product to market to this person right now?" type of system. It's pretty easy for a toaster guy to say "Amazon, show this ad to people who looked at toasters" without ALSO selectively hiding it from people who just bought a toaster. It's harder to pin down a pattern indicating the imminent purchase of a toaster. Like for instance, someone seems like they're probably 20 years old, and now they're looking at wedding stuff. They are probably going to be influenced by a toaster ad, but getting it to them would require a toaster manufacturer to set up some pretty complicated shit.