The main reason I am investing my time to update maps in my area (Michigan) is because Garmin/Navteq do not update their maps if you send them errors.
After YEARS of emailing map errors I am finally starting to see some progress by FIXING THEM MYSLEF
Supposedly the OSM ODBL terms would not allow anything but a direct resell of the OSM data. If Navteq tried to include its own fixes, addressing, etc, that data would have to be published for use by OSM. If Navteq sold OSM data directly, it would not make sense for anyone to buy it from Navteq if it could be downloaded for free.
I have been using Garmin GPS’s for 20 years and have been purchasing maps regularly (non free liifetime upgrade units)
I only ‘discovered’ OSM maps last month.
All of my GPS friends have not heard of OSM either.