Is Google's SpamBrain Algorithm Worth the Extra Focus in Your SEO Plan?
https://medium.com/@terryhutchins/why-has-google-search-become-so-annoyingly-bad-and-some-useful-workarounds-1ed319770225
If you have any experience running SEO long enough to get burned, you already know the vibe: you do everything “right,” then rankings wobble anyway, and the only thing that changed is you started getting bolder with tactics