Google’s John Mueller said in a webmaster hangout on YouTube that some links can become less important over time. The reason for that is that the linking web pages can become less important.
“[Links from other websites] don’t expire. What does happen though is that, especially if you’re talking about a large website that’s that’s growing regularly, then the pages that [that contain the ]links […] get deeper and deeper within this website
So for example, if you have a link from CNN and it’s in an article that’s linked on the homepage then that’s something that’s really important for us.
On the other hand, if this article is maybe a year or two later is somewhere in the archive at CNN then that article itself is not something that we would find that important anymore.
So it’s not that the link expires after a certain period of time, but just often that the page where that link is on that becomes less and less relevant over time, if it’s on a site that is growing fairly regularly.
But given that the page doesn’t change, or if it’s an important page in a website then it shouldn’t have any different effects over time.”
You can view the video here:
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