
It is rare for a comic strip or book to spring out fully formed, composed in perfect panel order. Comics are both written and designed, and a sure sense of totality has to exist before even a rough version sits securely on the paper (or the screen). The elements of the universe of the page may be very complex, no matter how small in scale.
While it is possible for a single panel to move from sketchbook to print with little alteration, the composition of a sequence introduces a separation of task and labour, even if only one person is doing it all.