Creative Generative Will (CGW), the Will that is responsible for the birth of and the continuing existence of the cosmos, desires to express its intention which is to be creative and wilful. Thus to facilitate this intention for creation, it wants to increase the number and variety of things in the cosmos, specifically things that can be creative and wilful themselves (such as humans). For this desire/intention it has created, and continues to sustain by pure willfulness, the manifold atoms, chemical elements, biological life forms and human beings thereby providing more variety with which to create new things (if you had a spreadsheet of all the possible combinations of things that could exist in the universe, you would have more permutations than if you just had two atoms rattling around).
In order to be able to manipulate all of this matter, all of this variety, CGW benefits from endowing creatures with self awareness (i.e. the ability to perceive/discern oneself relative to other things in the cosmos). This allows those creatures with self awareness (SA) to modify themselves and, or the environment so that they may be more creative and wilful. For instance a painter will not be a very good painter unless they exercise good motor (muscle) control, so that they can manipulate the paint brush to apply paint to the canvas. To be able to exercise proficient motor control first they must be aware of their arm, hand and various other muscles. This awareness of elements of the self is SA.
However before the individual can manipulate the environment or themselves, they need to create, which requires willfulness, but not SA. Willfulness to the point of being unaware of oneself, this is called single mindedness (SM). Single mindedness is comparable to being 'in the zone' when an athlete is running along a racetrack: they have become totally unaware of themselves or their environment, they are running on pure instinct, pure will, pure SM. Thus SM must exist before SA can occur, as SA needs something (a body to exist, an environment to exist in, and something else outside of the body to manipulate).