For my rag die, I deliberately rotate the die every few cuts; due to the grain of the fabric it tends to leave fibers behind on the leading and trailing edge of the die and not the sides. So I flip it around and run it through and that somehow seems to clear the fibers out of the sides (that were front & back before). So it sort of evens up the fiber shedding and keeps the blades more cleared out. I think it'd probably cut fine if I didn't do that too, but I do it anyway. I don't think it matters at all which direction you put the dies into the machine for most of the block type dies. Strip dies pretty much have to go in a certain way but for squares, triangles, rectangles, circles...I don't think it matters.