The notion that is generally considered better for vocal music is horizontal motion. This means that the voices move independently of each other, creating distinct melodic lines. Horizontal motion allows for clarity, individual expression, and a sense of independence among the vocal parts. This is particularly important in vocal music where the lyrics and emotions need to be effectively communicated to the audience. Vertical motion (harmonic progressions) also plays a significant role in vocal music, but it is often the horizontal motion that gives the music its melodic and expressive qualities.
