[OSM-talk] Proliferation of path vs. footway

[David Earl]

2009/8/11 Frederik Ramm <frederik at remote.org <mailto:frederik at remote.org>>
>     On the other hand, if your desire is to change something that already
>     exists and ask people to tag it differently from now on, or even worse
>     if you want people to agree on a blanket automatic change of millions of
>     existing objects, then you'll have a much harder time convincing people
>     that this is required.


I think we are at a turning point now.

Up to now, we could get away with changing existing tags, but as people 
start to use OSM for real world tasks and base software on it that is 
outside the OSM community, like other file formats, we really have to be 
more controlled about upward compatibility and support. People won't use 
OSM if we keep changing it in unexpected ways under their feet.

We may realise we made a mistake doing something on way and not another, 
but we have to take into account the impact and cost of changes against 
the perceived problem something causes.

For example, changing highway=gate to barrier=gate. That allowed for a 
consistent way of presenting barriers, but at the expense of anyone 
relying on gates to block routing through them for example not working 
(and if they weren't aware of the change - why should they be? - theior 
programs stopped being effective). This was a largely cosmetic change, a 
change for tidiness sake, not because it was necessary.

Changing the common tags like footway/path or the main highway 
designations would be a disaster for these reasons.

Consumers (people and software) want to have confidence in what we 
provide. They are worried about that from the point of view of people 
adding incorrect map data or not having complete map data, and breaking 
their software because of an arbitrary incompatible change adds to this. 
We need to live with our quirks, poor choices and so on more as time 
moves on.

David