A normal wooden spoon with a flat surface offers alot of resistance to the dough; and normally the dough sticks to the spoon, all of which makes the task of making bread quite hard.
The Danish dough whisk is an open spiral shape that allows you to incorporate flour into a thick dough with much less resistance. The dough doesn’t cling to this whisk as it would a wooden spoon. It makes it easy and simple to do a difficult task.