At the design level, it is a bit of a personal choice. A design that you like is a good one. But at the carving stage, the meaning is very specific: the edges of the debossed (cut-in) stamps all have bevels that compress the clay around the stamp and prevent cracks at the corners. Indeed, none of the lines and patterns cut into the stamps and rollers are laser cut (which always leaves a burned vertical wall, which then pulls up the edge of the design.) All MKM stamps are cut with cutting blades that leave a bevel for all the lines and patterns. So when the MKM stamp pulls away from the clay, or the roller is rolled over the clay, the MKM tool releases perfectly without pulling up any edges. As well, our stamps and rollers are scaled to work well in the realm of functional pottery - these tools are not re-purposed paint rollers - they are designed and made specifically for the clay worker.