A common discussion topic is, what do artists owe their fans?
I am an author — though one without fans at this time — so I am going to chip in my two bytes on the subject.
An author does not owe any far or reader a signature, a signed book a reading, critiques of unpublished stories or ideas. Some author do these things, but it is not an obligation it is what they want to do and I suspect what they like to do.
An author doesn’t owe anyone personal appearances, club meetings, or courtesy any not expected in just normal human interaction. (Sadly, courtesy is falling in disuse among people in general.)

What an author does owe his readers and fans are two things.

One, a complete story.
Two, that the story is written to the best of his ability,

I did not read any of the Harry Potter books until the final one had been published. I did not want to start a story without knowing if the author was going to finish it. (I once read a very good book series where the last book written ended in a cliff-hanger and now seventeen years later it has yet to be completed.)

This is all a writer owes his readers, but unfortunately there are authors who fail in even these simple requirments.