As stated, the Dashboard is a special Confluence Entity, as:
So, You might wonder If You want to use the Dashboard at all, or use a Page instead, there are not so many good reasons for the first, as (in my opinion) using a page has most benefits.
Above, it is claimed that "Is the Default landing page, and still - not always...." , this is why:
When user lands on the Confluence URL root, like http://www.mysite.dk/ or http://www.mysite.dk/confluence/ they are redirected to the Space determined in Confluence Administration -> Configuration -> General Configuration (Site Homepage):
Whereas, when a user in Confluence click on the "Dashboard" in the Breadcrums:
they are redirected to the relative URL /dashboard.action , displaying the Dashboard, nomatter what is set in the General Configuration.
This is for me not logical, and for the developer someting to take care of.