During a migration, everything has changed (all URLs), but not everything that has changed is necessarily a hugely significant change for users, especially if the Industry Email List redirecting URL is already classified as “not important” with a low frequency of “material change”. According to a recent Google patent: In some cases, search engine outdated content may have no special meaning because the changes to the documents listed in a search result are minor or the Industry Email List relevance of the documents remains substantially the same. Would it be the end of the world if a page that hardly ever changes, or only changes a few dynamic bits and chunks while loading, redirected from the index? Probably not.
The user still manages to reach the landing page from the search engine results pages through your redirect, so their experience is not significantly Industry Email List reduced. Your 'unimportant' pages can actually add a lot to Industry Email List your pre-migration visibility It's likely that the current rankings of longer-tailed queries (which can add up to a lot) are in place due to many minor signals picked up by legacy crawls on mature URLs over time. Important pages are crawled quickly after a migration, while the majority of low to unimportant pages (which may include low or no PageRank) combined add huge amounts to overall visibility.
This can include materiality votes (e.g. from the Industry Email List only internal linking structure), which will be everywhere. internal link signals report Signals used for ranking purposes from these will only be delivered to newborn URLs after crawling and updating on the search engine. It will take some time for all the pages of low importance (but contributing to Industry Email List visibility) to be crawled. And what about those pages from your old site that you may not have indexed before before the migration? They probably brought something of value for visibility. Gary Illyes commented in the recent