Why is sound so important?

Sound is what we hear. However in a film, the sound scope can be modified by using sound design that enables us to have suspending disbelief to create realism. 

We watched an Action film title sequence twice - once with sound, and once without. The one without sound was boring and didn't interest me at all. It took me a while to find some engaging shots, but even then, it wasn't worth watching for entertainment purposes. On the other hand, the one with sound really attracted my attention from the very beginning. The fast intense music was perfectly synchronous and it suited the action genre of the film. In some aspects, sound gives clues on establishing the tone and the atmosphere. It gives hidden clues that help the audience unravel the plot. It may also sometimes foreshadows key events that occur later in the film.  

The conclusion that can be made from these results, is that sound is a crucial factor in making a successful film. George Lukas, the director of Star Wars franchise, also agrees with the statement. He believes 'sound is 50%' worth the overall film production. In other words, sound makes up half the production of the film and without it the film would only be able to achieve half its full potential of what it could be.