A state is a billing region, not a market.
Selecting New South Wales as a target does not mean competing in one auction. Sydney, Newcastle, Wollongong and regional NSW behave as separate markets with different competitor sets and different costs to win a click. When they share a campaign budget, the cheapest region absorbs delivery and the metro that matters most gets starved. WIF separates the regions that need their own budget line from those that can safely share.