You can view a report that tells you if your site has 'broken links', or links from one place to another that are invalid.
You can view the report to easily locate any broken links on your site, and then go to fix those links. You should manage your site so that there are no broken links. If your site has broken links, you may frustrate your visitors, and give them the impression that you do not operate a professional web site. If you fix broken links, you can provide your visitors with a site that works and doesn't give visitors frustrating error messages.
You might want to view your report on a regular basis, perhaps weekly, and then fix the broken links. Because Web Builder Express can automatically manage all the links in your site that control navigation, you probably won't have many broken links. However, the people who update your site can add links manually. The location of data inside and outside of your site can change over time, and you should periodically review the broken links report to fix any broken links.