Currently the navigation of Liferay's sites is page centric. That means that there is a 1 to 1 relationship between pages and the site navigation. In order to publish any content in a site, it's necessary to create a page for it, choose the appropriate portlet to display and configure it.
This is especially limiting when trying to publish many content, since it forces for the creation of many pages. While using Asset Publisher along with display pages, may solve this challenge in some scenarios, it's not a feature that is easy to discover and use.