Google says if a core update has impacted your site, you “don’t have anything wrong to fix.”“There’s nothing wrong with pages that may perform less well in a core update. In fact, there’s nothing in a core update that targets specific pages or sites. So you can’t “fix” a core update. But suddenly, you see a shift in the reward process (like a core update), and you need to do the right things better than the others – you need to be least imperfect. There are no guarantees that a core update won't shake things up for any website, but you can prepare.