Let me try to explain…
throughout the series we learn random and seemingly meaningless things. A lot of them.
At the time you stopped reading there are probably about a 100 un answered questions… some remain answwered, some are forgotten…
Reading through to the end makes you expect answers… All the real questions he poses lead up to the big finally…
And it comes about in a rather lac luster way… You see the pages dwindling, and you don’t know how he is going to wrap it up in such a short time (having took 1000+ pages explaining all kinds of seemingly meaningless stuff) and then it happens…
No ultimate question, just an ultimate end.
SPOILER ALERT.
Some crazy group of aliens that set out on a war before hyperspace travel was invented (requiring cryogenics) got hit by a meteor half way through it’s long ass trip, and through a series of unlikely events, they wound up not knowing who they are, and monotoring earth intensely and not knowing why (they only remembered fragmentsof their purpose because the computer that held their brains got messed up).
Anyway these aliens decide that the y don;t want to watch earth, because it’s stupid, but they cannot forget the fragment of info they have, so they use their mysterious weapon to destroy the second earth, aswell as the entire plural sector of space time…
(sector 9 J plural z alpha).
It turns out that the plural sectors exist on the fault lines of probability waves in the great mish mash, and whe the wave breaks so do we.
There is no ultimate question at the end of the book, only an ultimate end…
The last thing in the book are the vogons checking a box on a form, signifying that the plural sectors were successfully demolished, which was a long standing order…
Doug Adams probably thought that the ultimate question was in fact, “what is the ultimate question”
If there is an answer to that question, then the answer is the most important, and this question is the second most ultimate or important.
I think when douglas adams started writing, he knew he had nothing to answer by way of “ultimate”. why else would the ultimate answer be incomprehensible?
Marvin came to an end, a very intereesting end… Gods last message to the universe was this: “Sorry for the inconvenience”…