Friction is essential for initiating rolling motion on rough surfaces, but once an object is rolling without slipping on a horizontal surface, it does not require static friction to maintain that motion. The concept of "cold locking" between the surface's features and the object's surface allows for rolling without slipping. In an ideal scenario, if the object's rotation matches its forward speed, the point of contact has zero velocity, eliminating relative motion and thus friction. However, real-world factors like deformation and rolling friction will eventually slow the object down. Therefore, while friction is crucial for starting rolling, it is not necessary to sustain it on a horizontal surface.
