All successful art is aimed directly at its audience. Whether the goal is to please, challenge, offend, or just create controversy, the artist has to know his or her audience in order to effectively evoke the desired response.
This goes for GMs as well. Luckily, our audience is pretty small, and we get to talk to them on a regular basis. We usually get immediate feedback, both positive and negative. And we usually have the flexibility to change things on the fly (unlike, say, a sculptor or an architect).
So, how well do you know your players, both collectively and individually? What do they want from a game? What don’t they want? Do you just know what they’ve said publicly, or also what they don’t necessarily talk about? How much can you can push them before they start pushing back? Do you know how they’ll react to the unexpected? Anything I missed? Sound off and let us know!