When you go to #Commons as a reader of one of our language projects, it helps a lot when the user interface is in your language. The quality depends of the localisation as it is made available at translatewiki.net. The quality also depends on the quality of the language support of your computer.
This example shows that our community works wonders where it can. We need the Wikimedia Foundation in its role of a 500 pound gorilla to push the quality of the software we run our systems on. This language is "only" spoken by some 37 million people and we want computers and telephones for them to have the best user experience.