I'm guessing the language for a start mate
And kph vs mph etc

On iPhone using Tapacrap

 

"Rest of World (RoW - Left Hand Steering)" does not really make sense for language setting, do you think? Also, the language can be set without VCDS and my car is displaying English even though the Instrument Cluster Country setting is "Germany"...
Germany uses kph, but so does a lot of other countries, so there is more to it than that.

 

It was only a guess

On iPhone using Tapacrap

 

Yes, my first thought also
It could be some regulatory thing, they really have a lot of those in Germany :? Maybe it decides what visual/audio feedback the instrument cluster should use :?:

 

I just read that it's possibly related to service intervals
How or why I don't know

On iPhone using Tapacrap

 

From searching around the Internet, it seems to affect things like seat belt reminder style and door reminder on/off as well as setting a default for language, units etc.