Documentaries tell a story as it covers an issue. A combination of a good story and storyteller has the making of a top-notch documentary. Documentaries are relatively easy to record the interviews and recount them to develop an interesting story. The trick is to make the story visually interesting, not just a string of talking heads. Although recognizable voices and faces can carry a documentary, interesting shooting, lighting, graphical elements, and editing techniques will create a well-rounded show. Good musical scoring can pace the program and create the proper mood.
Documentaries also require a good wrap, one that summarizes the main points of discussion. You can leave the viewer feeling ambivalent, but you should not leave the issue totally unresolved.