In adventure design, we tend to choose either to describe an environment or a solution. An environment makes no assumptions about how the players interact with it. A solution does. (e.g. the party fights the guards to enter the king’s halls)

Now, you might think describing an environment is better. But it is not without its drawbacks. Especially, as the environment gets more complicated, it also becomes more challenging to run.

We restrict freedom of action so we can present information in a way that GMs can run scenarios more easily.

This is something of a continuum, and elements of one style can creep into the other. A good example of environment adventure is "The Village of Hommlet".

Actually, when I say "good", I'm not quite sure if I mean that word. Because DMs can have real problems with it.

Yes, there are cultists in the village, but what are they doing? That lies with the DM making decisions. And because the scenario doesn't explicitly explain their actions, DMs can struggle with this.

(I do know that, as a novice DM, I *really* struggled with trying to find a way into both Keep on the Borderlands and Village of Hommlet because they assume a certain style of DMing).

The "trouble" with saying "This is what the cultists do if the players don't interfere" is that the players will interfere, and you go off the map and back to the DM determining actions.

Which is to say, it's not always a problem, but talks about DMing style and information.

DMing in a living setting, where the monsters react to player actions, is a fine style of DMing, but it often requires to you go beyond what is written on the page.

Sometimes you think you are designing an environment, when the actual usage is more in the "solution" scheme. Dungeons are a good example of this, where each room lives alone, doesn't reference the others, and pretty much predefines the outcome: "you fight the orcs".

This is not to say that dungeons CAN'T be environments. They certainly can be - but their presentation can make a big difference, as well as the desires of the DM.