Every great adventure story needs a level of surprise and suspense. Just narrating the accounts of somebody else's exploits isn't enough, no matter how intriguing the character. The trick is to give the reader an adventure of their own.
Plot twists and cliffhanger chapter endings are a common device that help create that sense of discovery and they can be very effective. Coming up with these bits and pieces isn't all that difficult for any writer that is practiced in their storytelling. The real hard part is gauging how well the presentation of them works in the end.
As the inventors of the suspenseful scene, we the writers are NEVER going to be surprised by own our story. Because of this cruel twist of quantum mechanics, there is the inevitable internal debate over whether or not you've pulled off what you were trying to accomplish. So we tinker and toy endlessly with it, banging our heads against the wall until finally we entrust it to another reader. Then there's a lot of finger-crossing and hoping, and in the end, usually a lot more tinkering to get right.
There's a balance that needs established and that's what the search is always for. (The Hunger Games is a great example of suspense done to perfection.) The action can't be too predictable, yet it can't feel like it comes out of nowhere which threatens the story with ridiculousness. These are the agonizing moments of the craft. The puzzlers. Does it work or doesn't it? In the end, you simply have to have a feel for it. Because after all, a good deal of writing is about going with your gut feeling.