Why do we need OSM Open Street Map? Why is it a good resource? Why is it free? There's more ....
The decision to use and work together to implement the OSM platform has motivations behind ethically relevant, read this interesting article BY Serfe Wroclawski, co-founder of the OSM project:
http://blog.emacsen.net/blog/2014/01/04/why-the-world-needs-openstreetmap/