Why does Google tip us off to search updates with minor ranking impacts but surprise us with the major ones?

It is the updates Google does not give us huge lead time to prepare for that impact the rankings the most, like the core updates, the Penguin and Panda updates from the past and most of the updates that go unconfirmed or unannounced.

Please visit Search Engine Land for the full article.

https://searchengineland.com/why-does-google-pre-announce-search-updates-that-have-minor-ranking-impact-378444