Answer: Stationary Microphones and Wiring
Step-by-step explanation:
We've come a long way in the movie industry from still pictures to motion pictures with no sound to motion pictures with sound. When sound was first introduced into movies however, you can imagine that the technology used was not as developed as it is now.
Microphones were not as mobile as they are now so movie stars had to either stand at certain locations to use the stationary microphones placed around the set, or they had to be careful not to get the wires of the microphones in their clothes all entangled.
This impeded the movement of the actors and actresses and needed some getting use to.