The placement of material has an order known to the owner. Leaving things out visually reminds us of the task needed to be done. Leaving it in a certain place denotes priority. Finish one task before beginning another. Creative thinkers often work on several projects at once allowing the creative process to develop at its own rate.
Completion can sometimes be an issue.
The end result is often more dynamic. Handle each piece of paper once. People need time to incubate information and make decisions. Putting papers aside allows us to formulate opinion on more than one level of thinking. Recognize this and deal with it.