My mother was a violinist.  She used to tell me how she had to practice standing on a stool to be out of reach of my hand disturbing her bowing arm.  She would walk up and down the room, eyes closed, passionately engrossed in the Bach Chaconne (from the Partita No. 2 for unaccompanied violin) or her rich full tone would articulate the rocking and swaying of the sonata by Franck. […]

Through hearing my mother repeating and repeating a phrase until the sounds felt right, I learnt the importance of the discipline of practice.  Drawing can sometimes be treated like the practice of a musical scale.  The discipline is to select and then concentrate on one particular event that is happening to a line or to a tone or a shape.