Structural dependency and structural integrity are what exist in nature.
Thus the only way to draw that imbues such natural order in drawing, is to follow structural order, which has its roots in structural dependency.
Even if the pencil does not follow that order, the brain has to go through such orderly thinking. That is the only way to ensure ACCURACY in one's drawing.
Thus the mastery of drawing involves a clear understanding of structure, that goes into 'structural clarity' (simplified definitions of structure that makes managing structural integrity feasible), and countless passing through of structural order, in thinking.
The final goal of the journey, is to arrive at a drawing that is NATURALLY SOUND.