It's hard to say how positions are rotated and changed within my workplace.  I work as a caregiver and have been with the same family for almost eight years now.  When I first started, we had an overseer who was with the family for a decade before I came into the picture.  Since her position was no longer needed because mine molded into one that I could not only do my job, but hers as well, my family let her go.  I think depending on the company (or family in my case) and their needs, positions, work functions and titles will always be changing.  And since we are all moving ahead with technology and social media, it is easier to keep things more organized as well as a better handle (to a certain degree) amongst our competitors.
As far as a leader holding their position for a long time, I definitely think it is possible.  But they have to have the skills or the willingness to except and integrate changes if needed.