Originally Posted by McMuttons
Often the game really was a game of players vs. DM, as they loved to try to find ways around things I'd planned in ways that I hadn't thought of, basically trying to break my adventure. It required a lot of quick thinking to deal with that. And taught me a few things about how to develop flexible adventures.
I had to learn to be flexible very early in my GMing career. I found out the hard way that if I built my adventures too structured and the story required the party to go "left" ... They always, always went .... "Right"!
From there I built my adventures around a series of scenarios that I could introduce at the right time, no mater if they went left, right, up or down