Since man sought to organise themselves beyond family groups, geography has been the fundamental organising principal of almost all the institutions created, it was really the only thing that made sense. Everything from businesses to empires and the church(s) were geographically organised structures.
Since the 70’s, many commercial institutions have attempted to reorganise along a customer or product driven logic, largely with limited success. Geography and the transaction costs associated with removing the natural barrier of distance have conspired to make it difficult and costly, and the old management silos are hard to break down until the enterprise is in real trouble, as IBM was in the 80’s.
For the last 10 years at a huge rate the net has removed geography as a significant driver of organisational structures. It simply makes no sense to now have multiple overheads in neighboring geographies, when the net tools enable the sharing of everything immediate.
The outcome, structure your organisation to focus on what keeps it alive, customers!