This is a very simple action but it can be quite effective in helping to make a site/materials clearer.
Each year, when Blackboard modules are rolled forward, content is copied across from one year to the next. It is important to remove any content and links which may not apply to the new cohort as otherwise the site can become very confusing.
In the below screenshot (taken from an existing module), you will see two links to discussions (Discussions and Discussion Boards) and two links to tools.
Rather than noticing the content itself, a student will likely first wonder why are there two links for the same thing in the same menu? Also, in the case of the discussion board when you click on them they are both empty, which makes it all the more confusing to students.
If you remove (delete or hide) the redundant links, the menu becomes much simpler to navigate.
The Blackboard Manual gives basic instructions on how you can add/remove/rename items in the main menu to make it simpler.