Every webpage you create is going to have links on it and outbound links benefit the site you are linking to. But what if you delete those old pages? If you delete them you also delete those links that were acting as your website's ambassadors of good. When it comes to your webpages you should always lean toward keeping them and only delete pages after careful consideration of what it might do to your outbound links and your sitemap. This will keep the sites you link to happy and will also keep your navigation from getting broken.