What I cannot figure out is why Amazon is not able to tell what I purchased on their own website... Why don't they have a "things people only purchase once" flag to avoid trying to sell me the same watch or pair of shoes twice in the same week?

The cohort for someone repurchasing the exact same item within the following month is probably a lot higher than just showing an ad for some other random item. This probably isn't a number like 20% more likely, it could be like 500-1000x. There may just not be enough data to exclude specific products. On the other hand retargeting companies definitely are over selling inventory to non sophisticated clients that should be excluded.

Targeting definitely works. A big entrepreneurial mistake is looking at things through your own eyes instead of those of users. Many brilliant coders can't get a handle on the business stuff because they just assume everyone else thinks and behaves like they do.

> Many brilliant coders can't get a handle on the business stuff because they just assume everyone else thinks and behaves like they do.

Ironically, the successful products I've created in my career I built to please myself. The ones I built to please others have all been failures. Apparently I'm not the unique snowflake others allege I am :-)

But what has been your target audience? Grandma or fellow John J. Hacker?

What I really detest in Amazon Adverts, is the tracked adverts for stuff they wont sell to me. I live in Switzerland, and some things I can order at amazon.de, others not. I often only find out at checkout which it is. So lets say I want to buy an SSD, I shop at amazon.de, find out they won't sell/ship it to me. Then for a month I get followed by amazon adds for that SSD that they wont sell to me.

Sometimes, when I'm angry at Amazon, I deliberately window-shop all those expensive feature phones from the mid-00s that Amazon still has not pruned from their database. For weeks the whole web will be decorated with ads for the fast-forgotten technical marvels of the past and there is that stupid little satisfaction of seeing what is supposed to be the greatest AI in existence filling the tipjar of websites for putting my eyeballs on pictures of a Walkman phone.

The Amazon.de branch is especially bad at this. It got worse with the new EU VAT that differs for every country, most third party vendors on Amazon.de ship only to destinations in Germany, but not to neighbour countries. Only on the checkout page Amazon.de shows one that they won't deliver the item - very bad UX.

Exactly. I recently bought a pair of bluetooth headphones form Amazon, and for weeks after I was getting stalked by ads for bluetooth headphones from Amazon. For a product I'd just bought. From Amazon.

> The reason you saw ads for them is because advertisers don't know you bought one, not because they do.

Given the amount of tracking they do, I'm surprised this is still a problem.

These algorithms do not work on 'specific people' or 'specific products' they work on vast buckets of A/B tested users with equally vast buckets of products. That's why you will get these 'bugs', which can be fixed by much more specific targeting (soon, on a website near you).

I think retargeting ads can tell that "you're you" and are capable of having implemented such check as a condition for not showing. But I don't know for sure, I only had to deal with them once at my work, when the boss asked me to put some magic hash number in some frontend code.

> soon, on a website near you

Yeah, screw you advertisers. I honestly tried to browse with ads, but I couldn't any longer and finally reinstalled AdBlock a few months ago.

> finally reinstalled AdBlock a few months ago.

Amazing you held out that long. The difference between 'with ads' and 'without ads' is so large I can't understand how people in the tech scene (for who it is trivial to set this up, luckily for the advertising industry not all that trivial for others but getting easier all the time) still browse without some kind of blocking. Besides the security implications of running third party code on just about every website.

Call it well-developed banner blindness. Too well-developed, I'd say, as I caught myself at times (and ended up in an IRC flamewar once because of it) missing pieces of content because they looked too much like ads. It's amazing how your brain can learn to filter out the noise before it reaches conscious level. I also don't care that much about security implications other than malware. All that combined with me a) generally not visiting mainstream sites, and b) being too lazy to install a new extension meant that I managed to run without ad blocker for a few years.

Ultimately it was YouTube ads that play before videos that were the last straw; I sometimes run YT as music source and I got too pissed off about having to listen to 30 seconds of unskippable advertising in order to get to 120 - 240-seconds long video. Mostly it's mood-breaking.

I looked at a number of faucets online from the same company. The only one I later received ads for was for the exact one I actually bought.

He looked at faucets a few months ago, then stopped. What does that sound like to you?

The question is whether this additional effort is strictly necessary or whether it’s just nice to have.

Why do complicated things when something simple already works pretty well? Your thinking that just because something is possible it will be done is not very close to the practical reality in the trenches. Because something is possible it might be done if resources are there. If not, best effort, done.

All of this analysis is expensive, so don’t expect it all to be done.

How do you detect the absence of a visit if all you have is a hidden pixel on a page?

Okay, let me rephrase. If you have tracking pixel logs that show his having searched for faucets for a while, and then that stops, what does it sound like?

Theory A: He wasn't shopping for faucets at all, he's just a bot following links and who had recently visited a faucet portal page.

Theory B: He searched, found a faucet he liked and bought it.

Theory C: He searched, then installed Ghostery, and is still in the market for a faucet.

All are possible, but one of them sounds a lot more likely than the other two to my ears.

Let's assume Theory B is correct, and searching for a faucet and then stopping can be treated as having bought a faucet. That tells the advertiser that the user buys faucets, and that's exactly the right person to advertise to. I'd bet that in a large number of cases someone who buys a faucet is likely to buy another faucet in the near future - faucets are something that you buy when you're doing up a house, or you've moved house, etc.

Advertising to someone who you have reason to believe is going to buy your product is much more effective than advertising to an unknown person.

>>Advertising to someone who you have reason to believe is going to buy your product is much more effective than advertising to an unknown person.

Totally depends on the product and the person you are marketing to. Marketing hammers to carpenters makes sense: they use many different types, and presumably go through them quickly. Marketing faucets to regular folks is a dumb thing to do. A faucet is something you buy once in a blue moon.

Also, the fact that he bought a faucet means he probably owns a home. And is much more likely to have to buy a faucet again than a random person who may rent and never have a reason to buy a faucet.

No I don't think that's a mistake. I suspect the probability that someone who has recently bought an item buys the same one or a similar one again is pretty high.

People buy stuff for others. People buy stuff for professional reasons. And yes people do need more than one faucet when they are building or redecorating a home for instance.

Also, showing people stuff they have recently bought may provide an incentive to recommend it to others or write a positive review online.