Movement involves judgment. Just imagine the multitude of situations in a child's lifetime when they will have to use these skills. But the problem solving is not just at this surface level. These are all examples of decision-making that is needed in school, and social life. It is through movement that the ability to problem solve first develops.
Motor develop builds more than just their muscles.
A bit about Graphomotor Graphomotor is similar to fine motor skills but focuses on writing skills. Skills needed to use scissors or a needle are much different than the control needed to use a writing tool. Graphomotor skills not only involve the flexibility of the finger muscles but, also, the ability to keep up with the flow of ideas. How frustrating it must be to not be able to write down what you are thinking.