Why did Ernst Lubitsch film some sequences without dialogue before dubbing in sound?

Ernst Lubitsch filmed certain sequences without dialogue and dubbed the sound in later to overcome the technical limitations of the early sound era. At that time, most directors were forced to keep their cameras in soundproof, stationary booths—often called "iceboxes"—to prevent the noisy whir of the camera from being picked up by microphones.12

By filming sequences without dialogue, Lubitsch was able to free the camera from these restrictive, soundproof boxes and static positions. This technique allowed him to maintain the fluid, dynamic camera movement that characterized his work, rather than being limited by the need to record sound and image simultaneously.12