Broken link
A broken link points to a page that no longer exists or can't be reached, so whoever follows it, person or bot, hits an error.
A broken link is a link that points to a page that no longer exists or can't be reached. Click it and you land on an error, usually a 404. It can be a link between two of your own pages, a link from your site to someone else's, or a link from another site to a page you've moved or deleted.
Broken links cost you twice. People hit a dead end and leave. And crawlers spend their visits on pages that aren't there, while links from other sites that point at a missing page stop helping you.
How links break
Most break for ordinary reasons. A page gets a new address during a redesign, a product is discontinued, a blog post is deleted, or another site you linked to changes its structure. Typos in the address do the rest.
The fix depends on where the link lives. For your own links, update them. For pages you've moved, send the old address to the new one with a permanent redirect. For pages that are gone for good, either redirect to the closest page that still exists, or let the old address return a 404 or 410 so search engines drop it.
Broken links and AI answers
AI answers cite addresses, and the platforms don't recheck every one each time they answer. When a page you've moved is still being cited, the person who clicks the link in the answer arrives at an error page on your site.
For example, Harrow & Pine renames its oak table page from /oak-table to /tables/oak-dining-table and doesn't add a redirect. For the next few weeks, answers about oak dining tables still link to the old address, and every click from those answers ends on a 404. A redirect would have caught every one of them.
In AnswerOrbit
Recommendations include fixing pages on your site that return an error to bots. If you connect your server logs, the Bot visits tab in Website shows the pages AI bots read and which requests failed.