What makes a good action/adventure story?
A good action/adventure story requires lots of... well, action! And adventure! LOL. No matter how long it is, it should move at a quick pace and be filled with exciting sequences and dangerous situations.
So many action/adventure stories can also be labeled suspense, in your mind what is the difference between the two?
There's often an overlap between these genres, but action/adventure is usually fast-paced, whereas suspense can be slower-paced, in order to build the suspense more. I like how Steph answered this question, also: suspense tends to be more mysterious; the villain may be unknown for most of the story, whereas in action/adventure, the villain is usually known, whether it's a person or the elements.
Have you ever written an action adventure story and if yes do you find them harder or easier to write than any of the other genres?
Yes, I have, and no, I wouldn't say it's harder than any other genre, but like all genres, it has its set of challenges. One challenge with action/adventure is thinking up dangerous situations to put the characters in and then finding a way for them to get out again. Another is writing with just enough detail so that the readers can picture what's happening like a movie in their mind, but not so much that the details slow down a scene that's meant to be fast-paced and exciting. I tend to write with a lot of description and dialogue, but in this genre, I have to use less of that and write more action.
If anyone tends to stay away from this particular genre, why?
Not me; I love action/adventure!