Google updated its search quality evaluator guidelines back in August, placing a greater focus on the ‘E-A-T’ principles of expertise, authority and trust.
The first few weeks of the update was characterised by leading brands witnessing significant and sometimes erratic changes in their organic search visibility. Some brands saw their visibility almost wiped out entirely, only to return to normal shortly afterward. Weeks of volatility followed as Google appeared to tweak the dials on the updated algorithm.
https://www.affiliateinsider.com/2019/01/25/google-e-a-t/
