is because the contents are then uniform throughout - you can always just take the one on the top of the pile. as soon as you are having to flick through the pile trying to find something, you know you have a problem. how many times have you gone through the contents of your in-tray over and over again before finding that one piece of paper you need? you can waste so much time and energy on this "system". time to think vertical! vertical systems are so much easier to use than horizontal systems, as it is much easier to see and access what's there, and much easier to add 