They can be made lighter than solid and spoked wheels, resulting in better handling, and less rotational inertia. The lack of spokes or a traditional hub also allows for more space, which can be used to more easily package a hub motor.
The design is lighter than solid and spoked wheels, improving maneuverability and reducing rotational inertia. The absence of spokes or a standard hub also offers more room, which aids in the placement of a hub motor.