These media have specific requirements that make them a challenge to distribute. The protocols of the Internet were an intelligent solution to the problem of distributing static files. Unfortunately, audio and video need to be played in a continuous pattern. The data needs to be interpreted in a specific order. Internet traffic is routed through the path of least resistance.
Packets often arrive out of order as a result.
This presents no problem when and entire file is downloaded. Smart network protocols put the data in the proper order when stored on the client machine. The problems arise when an application like a streaming audio player needs packets in a timely manner. If a file is playing and the necessary packets are not present there will be dropout. Dropout is the scourge of streaming technologies, those annoying breaks in the presentation of video or audio.