What specific property of motion does spinning the Bo facilitate?

Spinning the Bo staff facilitates the property of angular momentum. Angular momentum is the measure of an object's resistance to changes in its rotation. When the Bo is spun, it gains angular momentum which makes it more stable and resistant to changes in its orientation. This is what allows a trained martial artist to maintain control of the Bo during rapid transitions and complex maneuvers. This built up angular momentum also adds power to strikes. Since the Bo is already spinning, the energy needed to redirect the momentum into a strike is decreased, while also delivering a blow with a greater amount of force than simply swinging the Bo without first gaining angular momentum.