Choosing small groups of sounds and placing them in time is the simplest description I can think of for what musicians do.
Every sound has a set of pitches (very rarely a set of one).
The total number of perceptible pitch steps in the average (very subjective) range of human hearing, 16-16,000 Hz, is about 1,400 (the total number of notes in the equal-tempered scale over the same range is 120 (a piano has 88 -the range of the piano is 27.5 to 4186 Hz)), so even a musician “playing every note” is using a small group of perceptible pitches).
Every sound has what is generally called timbre (which despite rigorous work by numerous highly intelligent people remains “the psychoacoustician’s multidimensional wastebasket category for everything that cannot be labeled pitch or loudness” (W. Dixon Ward, Psychoacoustics, 1965)
Every sound has loudness (amplitude). Loudness is variable, subject to the duration of the sound and relative to its proximity.
Every sound occurs in time: attacks, has duration, and decays.
Sounds interact with other sounds and with the spaces in which they occur forming localized soundworlds. Once a sound enters the soundworld, it is subject to and integrated with the influences of its environment. Except under rigorously controlled laboratory conditions, no sound has a separate identity, from the instant it is made it is a component of the soundworld.
A musician participates in and influences a localized soundworld by choosing small groups of sounds and placing them in time (so does a passing driver —makers of music are just being more deliberate about it).