The dynamics are written instruction about the loudness of the music for the performer. A music piece played with no dynamics can be associated with a robot narrator reading poetry. The four components of the music sound are:
pitch, duration, loudness and timbre.
In fact the written music in conventional notation is showing, representing those main qualities of each music sound. If one of those four is not taken care of, we are not executing the music as the composer meant it. There is actually one of those four qualities that we can “ignore” that’s the timbre, because if you are playing music for guitar on a guitar then you are automatically doing it anyways…
It is essential to learn to take care of the written dynamics, to explore the dynamic abilities of your instrument, to develop a habit always to execute and relate the music with its dynamics.
You can make an experiment, learn well a piece with no dynamics bring it to the needed speed, make it flow and so… then try to apply dynamics …you will be surprised that first the music is totally different and second you will have to literally relearn some parts of it.