Neil Gaiman's Introduction to the "Ultimage Hitchiker's Guide"

"He was tall, very tall." Gaiman does not say so, but I think it obvious Adams was not at all sure of himself.  But, as Gaiman nails in his second paragraph, when you once accept Adams's view point, you're stuck. The legend goes that, while sleeping rough near Innsbruck on a university vaction, Adans thought "someone should write a Hitchiker's Guide to the Galaxy."  Whatever.  It got written, at least as a radio play.  The original vehicle was a series of plays in which the world, at the end of each, was destroyed.  Dramatically, the idea was unsatisfying.  The end of the world for something like the creation of galactic bypass demanded some consequence:  someone to care about it.  The result was the creation of characters who did care, and who would drive a much richer plotline.