The Motor Test program was modified to change the serial monitoring output message format and text, because I thought would be easier to understand for motor testing. It changes to text output to match the command name and prints them out with carriage returns so the text stacks on the screen. A space is also printed between each loop. The original program worked without the modification and this was changed for my preference, maybe yours. For some, this may be more of an example of Arduino coding practice than to produce a perfect program. Try it anyway, it will give you experience in the serial monitoring communication programming.