According to scholar Larry Sitsky, because the purpose of avant-garde music is necessarily political, social, and cultural critique, so that it challenges social and artistic values by provoking or goading audiences, composers such as Igor Stravinsky, Richard Strauss, Arnold Schoenberg, Anton Webern, George Antheil, and Claude Debussy may reasonably be considered to have been avant-gardists in their early works (which were understood as provocative, whether or not the composers intended them that way), but Sitsky does not consider the label appropriate for their later music.
[9] For example, modernists of the post–World War II period, such as Milton Babbitt, Luciano Berio, Elliott Carter, György Ligeti, and Witold Lutosławski, never conceived their music for the purpose of goading an audience and cannot, therefore, be classified as avant-garde.
[9] A prominent feature of avant-garde music is to break through various rules and regulations of traditional culture, in order to transcend established creative principles and appreciation habits.
Hint, metaphor, symbol, association, imagery, synesthesia and perception are widely used in avant-garde music techniques to excavate the mystery of human heart and the flow of consciousness, so that many seemingly unrelated but essentially very important events interweave into multi-level structures and forms.
[11] The 1960s saw a wave of avant-garde experimentation in jazz, represented by artists such as Ornette Coleman, Sun Ra, Albert Ayler, Archie Shepp, John Coltrane and Miles Davis.