If you are talking, you cannot listen and you are disturbing others. If you are listening, you are part of the concert. The music - the creative work of a composer 2. The performers - the people who make the music sound and interpret the composer's ideas 3. The listeners - the people who hear the music There is more.
Musicians spend many years training and working to play music extraordinarily well.
When they are on stage, they need to focus on the music with total concentration. They can tell if the audience is listening well and are energized by an attentive audience.