On Twitter, Google’s John Mueller said that it was normal website maintenance to remove non-working links from your website:
Sounds like normal site maintenance to me.— John ☆.o(≧▽≦)o.☆ (@JohnMu) 31. August 2017
What is link rot?
Link rot is the process by which links on individual websites or the Internet in general point to web pages, servers or other resources that have become permanently unavailable. You link to a page and that page becomes unavailable over time. This is a normal process because people close their websites, websites get new owners, a website gets an update, etc.
Outdated links on your website is something that you should deal with. Google wants to show high quality websites on the search result pages. Websites that contain many non-working links aren’t high quality websites.
How to find these links on your web pages
The website audit tool in SEOprofiler shows you the pages of your website that contain links that do not work anymore. If you haven’t done it yet, check your web pages now: