When you have to pack all your stuff up, you uncover all sorts of things you’ve been hanging onto for reasons you can’t recall: take-out menus to restaurants that have closed, keys that open unknown doors, ticket stubs to plays you can’t remember watching.
Redesigning a website can be a similar experience - tools for projects that are no longer done, guides to courses that aren’t part of the curriculum anymore, links that go to web sites that are no longer there.