Office 2016 Default Save Location
Microsoft has been making changes to Office 365 subscription software settings. One of the changes that Microsoft has pushed is the default selected location of Office documents. The default location now is One Drive.
Default Save Location
Change on a Per install basis
You can change this default setting and save files to your computer hard drive or network drive by following the instructions below.
Open any one of the Microsoft Office 2016 programs
Click on the File menu item
Click on Options
Dialog box “Word Options” opens. Click on Save settings located on the left menu
On the right-hand side you will see a checkbox labeled “Save to computer by default”, check it and then click OK.
Now when you go to save a document it will default to your PC.
Registry
If you have a system that fleet of systems that you manage you can set the following registry in the HKCU to force the default to be off. There may be a policy definition but I like to understand what is being changed.

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\General\PreferCloudSaveLocations Set REG_DWORD = 0