He is easily swayed from his path by distraction and irrelevance. The definition of maturity is that our entire life is focused in a single direction. Every frame of existence is joined together into the film of our life. We see everything in life as part of the whole, not as separate journeys. A child is impatient for this exact reason.
Nothing seems to be going anywhere.
Every moment is katua, cut and separated from the next. His attention span is measured in seconds. The definition of adulthood is the ability to weld all of these snapshots of reality into a single cinematic flow. Being an adult means that we perceive everything in life is a single system, a single route-map, a single film. Being an adult means having persistence of vision.