Sometimes people comment upon the fact that novels are slightly different to radio serials of the same title.
Radio serials are dramatised versions of books – actors bring to life the various characters and sound effects are added for atmosphere and realism.
Therefore, scripts and dialogue have to be created for all the different roles; meaning conversation, narration, and interaction between characters require the words of the novel to be brought into the relevant form.
The other influence upon the script is that radio serials are just that – serials. Hence the story has to be broken into episodes (action points) and character names have to be used constantly to remind the listener of who is speaking or being spoken to (especially important when a listener tunes in part way through that day’s episode). Narration links themes and threads together but it is the all-important dialogue that brings life to a show.
It takes a talented writer to adapt a novel into a radio serial. Actors need to be skilled in acting into a microphone instead of into a camera lens. Audio Engineers require expertise in using audio clues to convey location, atmosphere and events.
And so yes, there is a reason for the difference between novels and radio serials.