Bedrockgames
I post in the voice of Christopher Walken
Well if the DM puts a ditch somewhere and then puts something on the other side of it and then puts an invisible force field blocking anyone from jumping the ditch...I have to say I agree that such a situation is a bit whacky. What else is causing the inevitable outcome other than DM desire?
Most examples like that are not so extreme. All he is talking about is the ability of the world to have hidden dangers and pitfalls (dangers and pitfalls you sometimes can detect if you are careful, smart or lucky). But it is not usually about the GM making playing "gotcha" or forcing an outcome. It is simply about making the world not always be fully predictable and maintaining a level of excitement.