Every routing system needs to answer: who owns this account? If the answer is unclear, signals go nowhere, inbound leads hit round-robin, and two reps call the same company on the same day.
Territory assignment should be data, not a spreadsheet. Rules in the warehouse, applied at account creation, with collision detection and quarterly rebalancing.
It is not glamorous work. It is the foundation that makes signals, inbound, and outbound all land with the right person.