Here's why:

* Dynamics refer to the loudness or softness of a sound.

* Volume is the physical intensity of a sound wave, which is directly related to how loud or soft it is perceived.

* Pitch refers to the highness or lowness of a sound, determined by the frequency of the sound wave.

Think of it this way:

* Dynamics are like the volume knob on a stereo.

* Pitch is like the tuning knob on a guitar.

While dynamics and pitch are both important aspects of music, they are distinct concepts.