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I just looked up Cookie and Kate. On my iPad I had to flick 7 times to get past the exposition on Crispy Roasted Chickpeas and find the actual ingredients. When I found the ingredients, they occupied a small squeezed sliver of the page. As I was counting the number of simultaneous ads surrounding the ingredient list (4 separate ads), a pop up covered them all and suggested I sign up for her newsletter. The recipe loo…
The problem is that Google started weighing time spent on page very heavily in their ranking algorithm - I don't remember at what point this happened but it must be about a decade ago by now. Every time a user clicks a Google result without using "Open in New Tab" and clicks the back button, Google gets a signal about how long they spent on the page. The longer a user spends on the site, the stronger the signal. Once…
Evaluating search is difficult because it's a tension: if users click a lot, is it because they find many valuable things, or because they didn't find what they were looking for?
If a user clicked just once, is it because they found what they were looking for or just that the rest of the results were so bad the user gave up?
The long click (user clicked, then didn't click again for a while) is a better metric, but also not ideal: did they stay because they found what they were looking for, or was the result just that confusing they had to stay to comprehend whether it was the right thing? Most often it's because they found what they were looking for, but the pathological cases hide in the middle: many similar correct results, winner is the one that makes the user a little slower.
(This has nothing to do with tabs or back buttons, by the way. It happens any time they can detect subsequent clicks on the search result page.)
I've worked in the search space (though on less evil projects than Google) and I still struggle with the question on how to evaluate search. If you have ideas, let me know!