With time, there are URLs which become obsolete. This happends when a content is removed or its friendlyURL is changed, when a page is removed or replaced, etc.
In these cases, customers don't want to lose the SEO positioning of their already existing URLs. They want ot take advantage of this positioning to redirect to their new URLs using permanent redirects instead.
Historically, this issue has been approached with a focus on 'Link to page' type of pages but it could also be approached from a wider point of view. For example, this could be achieved by creating a portlet to manage redirects with the option of selecting if the redirect is permanent or temporary.
This will give value to our customers as they will be able to evolve their portals without the drawback of injuring their SEO positioning and they could manage these redirects directly with minimal (or without the) intervention of other departments like IT.