Unlike the precomposed genres of Classical and pop/rock, jazz music, focusing mainly on improvisation, uses a melody and chord structure to set a topic; the artistry of it however comes in the performance and interaction between the musicians. Instead of some climactic speech with a story-like structure, jazz music focuses on the development of ideas and therefore may not be as linear in its performance. It can be compared to a situation in which academics or scholars discuss a certain topic at a conference; there will be some in the audience who follow the discussion very closely while others will pick up bits and pieces trying to absorb the rest for later study. From this point of view it is clear how this form of music is much less accessible to the average or casual listener.
Folk music is truly the most egalitarian of all the musical genres. At its best it speaks from no platform. There is no hierarchy or even need for appreciation. It sincerity is meant to be so exposed that any person can take part in it. There is of course very little intellectualism or detail from which to draw interest, and so its emotion and lyrical content must be compelling enough to hold the listener. While the other genres tend to create some sort of hierarchy between artist and audience, the folk artists provide a face to face conversation with those that they perform to.