Nothing like knowing where a post is going when I start.
First, I prefer beginnings. I like meeting new characters and anticipating a long and fruitful relationship with them. I like discovering where a story is going and hitching along for the ride.
Second, I prefer long books. I want time to know these characters. I want to be able to linger over them for days or weeks (like Charlie Bucket and his bar of birthday chocolate). If I spend close to 20 bucks on a book, I'm going to savor it like steak, not stuff it like popcorn. I am willing to give a book enough time to complete its mission and tell its story. If a book can't do that in the page count I allow, then the story needs to be revised a bit, In My Humble Opinion (I just figured out what those initials mean).
An addendum to Point Two is I don't like knowing I will be dropping 20 bucks for the next 7 to 10 years on a story line. You'd think I would, being very into Dave Ramsey and budgeting, but I once put a book back because the front page said "book 1 of 7" and the copyright date was that year. How do I know I'll even be alive for all 7 books? Or that the author will, for that matter?
Third, I prefer happy endings. When I finish the last page, I choose to believe all major problems are resolved forever and the characters have now learned the life skills necessary for future happiness. Real life is depressing enough. Let the fake people have their fake happy ending.
Sequels annoy me for the extension of those same three reasons.
A sequel is a continuation, not a beginning. Sometimes, it's an ending. Dune is one my favorite books. I read it four or five times as a teenager. I made the mistake of reading the sequel - aargh! What happened to everyone I love? Paul, my beautiful Paul! It's just wrong!
Sequels can be long, too, but they often provide information that changes your understanding of the characters from the first book. Assumptions are shattered, assumptions I've nursed the entire time the sequel is being written. Reasons are provided where you had already made up reasons. And that pesky "continuation" problem comes up again. Depending on the type of sequel, the main problem from the first book may not have been resolved until this book. I hate that. I hate cliff-hangers. As a sci-fi fan, I know a cliff-hanger can hang there unresolved forever if the network chooses to cancel the show. Finish your book, authors! You're not guaranteed another.
A sequel destroys any illusion of happy endings. A book worth reading is a book with conflict. Conflict means your beloved characters aren't happy. They haven't ended well. Their problems continue or new problems arise to plague them (why I won't read Star Wars books. Give Han and Leia some time to be together, for goodness' sake! They did help save the universe! They can't take a honeymoon? Sheesh)
So that's why I hate sequels. I say I intend to write them anyway, but my sequels will have one ground rule (only one? shocking!).
My sequels will contain characters from a previous book, but those characters will face new problems and resolve them within that book. Happily, if I can swing it; satisfactorily, if I can't.
Now you know what to expect from me and my books. Let's see if I can hold to it.