Am 09.07.2015 um 11:04 schrieb Gerard Meijssen:
Hoi, My understanding is that it is machines that need to uniquely know what a property stands for. People are quite capable understanding what a combination of a P and a Q mean. At that time there is no disambiguation. With proper descriptions it is not hard at all to choose the right property when a new statement is made.
That is not the use case under discussion.
The use case is accessing data from wikitext on the client wiki, using something like {{#property:date of birth}}. In order to do that, "date of birth" has to be unique.
For picking a property on wikidata, when creating statements, unique labels are not needed. That was never an issue, and never the subject of discussion.