It’s a very hard thing to do a good sequel I think.
First of all there is the very tricky job of trying to replicate the unique combination of factors that made the first one a hit.
Then second of all, not only do you have to replicate, you have to go bigger in each area as well because the expectations are so high.
I find most sequels are disappointing because the creators only start to consider a sequel after the original proves to be a hit.
I think the best way to avoid the disappointing sequel trap is to plan sequels before the first instalment is released.
For example Lord of the Rings, Harry Potter and Star Wars (the original trilogy).
