UKHeliBob:
How do you know ?Don't forget that the program runs when you upload it and on most Arduinos opening the serial monitor resets the board and it runs again, so by the time that you see the output the program has run twice.
YEP - the trick is to have the serial monitor already opened when you upload (and if you want to test initial conditions, change the keyword to something else so that the code does not assume the memory is already initialized from other previous trials with the same keyword)