They also list Google Sky Map ( https://gcemetery.co/google-sky-map/ ) which they call discontinued because Google released it as open source and handed over reigns to another group of developers, but looking at the github it still gets updates too, so I can see this one being either way. https://github.com/sky-map-team/stardroid
Another quarter were explicitly experimental (labs, glass, ara, etc.).
And another handful are products that no longer make sense in the modern world (google desktop, various toolbars, browser sync, the gmail notifier, etc.)
Hell, one of them is apparently the webconferencing software google employees used internally in like 2012, it wasn't a product.
How many years was Gmail in "beta"?