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Losing faith in OpenStreetMap

Posted by Andy Street on 27 June 2015 in English.

As a member of the OSM community for over nine years it is hard for me to admit but I’ve lost interest in contributing data to the project. I regularly spot stuff that needs mapping and I’m still subscribed to the mailing lists but I’ve not made an edit in months.

When I first joined OSM the map around me was a blank slate and all of my efforts were focused on collecting the bare minimum to create a functioning map (highway type, street names, basic points of interest, etc.). Getting out and about surveying streets was enjoyable and the OSM tagging system handled these basic details rather well. Over time as the number of missing features decreased and my attention shifted to improving the level of detail collected.

All was well for some time but as the level of detail increased so did the number of conflicts with other mappers and I have been increasingly aware of the limitations of the current tagging system. Some of the things I have learnt during this time include:

  • “Breaking” the the standard rendering is unacceptable and valid data will be removed to “fix” it.
  • Tagging uses a system of implied defaults that can change based on context, location and contributor understanding.
  • Explicitly stating implied tags (or even measurement units) for the avoidance of doubt is considered wasteful and will be removed.
  • Generic tags such as “name” or “ref” can be ambiguous when a single element describes multiple things (e.g. highway and bridge or shop and building).
  • Once a tag is adopted it is virtually impossible to change as data consumers will require a critical mass of mappers before adopting the change and vice versa.
  • There is no definitive tag owner to settle disputes. The community is supposed to reach a consensus but this doesn’t always happen.

As a result I am no longer convinced that OSM - in its current form - is capable of becoming the high quality data set that I aspired to help build. I’ve got a basic idea of how tagging might be improved but given the levels of inertia I am loathed to pursue it.