Unity, as a framework, can be used to build anything from small applications that require only a handful of sound effects and a single background track to huge role playing games that need millions of lines of spoken dialog, music tracks, and ambient sound effects. Regardless of the actual scope of the application, audio files are often a large contributor to the application size after it is built (sometimes called its disk footprint). Moreover, many developers are surprised to find that runtime audio processing can turn into a significant source of CPU and memory consumption.
Audio is often neglected on both sides of the gaming industry; developers tend not to commit many resources to it until the last minute, whereas users rarely draw their attention to it. Nobody notices when audio is handled well, but we all know what bad audio sounds like--it's instantly recognizable, jarring, and guaranteed to draw unwanted attention. This makes it crucial not to sacrifice too much audio clarity...