Do you have dead links at your website? Dead links are links that don’t go where they did when you posted them. Sometimes the site you posted to is gone, sometimes it has had a change of content that makes it less useful than it used to be, and sometimes it has broken. You should clean those up from time to time.
It needn’t take you long.
You can use the W3C Link checker to text all the links at your site in a matter of seconds. You simply type in the URL of your site and give the checker a little time to test it. If you have any broken links, the tool will tell you so.
Use the Broken Link Checker plugin if you have a WordPress site.
Going back and correcting the links is another matter. Sometimes you can just remove them, but sometimes you may need to search for the new home of the information you were linking to, or for a replacement for that link.
This is an essential bit of maintenance, though. Recently I’ve been seeking out good sites to link to for a client, and I’ve had to reject a lot of otherwise good options because they had a high proportion of dead links. You don’t want this to happen to you.