Earlier quoted context omitted.
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…
Yup. This is the Long Click metric. 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…
Why do you care as a search engine? This is a natural human problem that can't be solved with technology, only by humans.
It used to be, that I went to page 5 of Google instantly, because that was where the real results were. The first few pages were people who knew more SEO than sense.
These days, that doesn't work since "semantic search" because now it appears to be sorted by some relevance metric and by about page 5 you start getting into "marginally related to some definition of what you typed in but still knows too much SEO to be useful."
The point is, this was already a solved problem if you knew to go to about page 4-5. Then people started trying to use a technical solution to a very human problem.