Navigations which are utilized on multiple pages keep the same relative order on all pages, unless the user initiates the change. (Items can be removed or added, but they must maintain the same order relative to each other)
When observing navigations which appear on multiple pages, ensure that the relative order of the navigation items remains in the same sequence compared to other navigation elements.
It is okay (albeit not recommended) to have the contents of navigation areas change depending on the page. This criterion is only concerned that whatever navigation elements are visible on whatever page, they are in the same relative order that they appear in on other pages.
For example, a main navigation structured as so on the homepage…
Homepage
About
Projects
Contact
…compared to that same main navigation on an "About" subpage (where the "About" link is replaced by other links)…
Homepage
Leadership
People
Projects
Contact
…would be considered a passing implementation because the relative order of the repeating "Homepage," "Projects," and "Contact" links are the same.