Even though some sequels have been my favorite films of all time (The Godfather part II, Empire Strikes Back are just 2 examples) I have to agree with Ben. The underlying motivation for a sequel is to extend the franchise, maybe tell a good story too, but really it's mostly about money. Francis Ford Coppola made TG part 2 because TG 1 was a HUGE blockbuster, even though he did wind up making an even better film, IMO.
Well, as for part III....I won't get into that.

Although I do like parts of it. And the end still gets to me.
Pixar made TS 2 because yes, they had a great idea and knew that it would be much better as a theatical than a DTV....but they had to have known that it would make them tons of cash.
Ditto DW and Shrek 2. And no, I still don't buy that argument that they were originally planning to make 4 films....uh huh, right.
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About All Dogs, I still love that film.

Yeah the story sputters a lot here and there and by the end it's pretty much shot, but I just find some parts to be very heartwarming....I don't know. I just have a soft spot for that film.
I love Ann-Marie, she's so cute, and watching her animation as a kid and the colors of that film.....this may sound weird but ADGTH was one of the films that got me even more into animation, and got me to like it past the age of 13. So was an American Tale and Land Before Time.

Don Bluth in general....I just like the dark stuff in his films.
He should have stuck to that.
You can’t just have your characters announce how they feel! That makes me feel angry!