I'm catching up on episodes of Fear the Boot and just went through Episode 314, their GM Feedback episode. Asking for feedback after a game is an extremely valuable tool regardless of how long you've been running games. You will (should) always be trying new things, there will always be new players, things will always change (oh, you have a group that's been together 20 years? It takes 4 years for your body to replace every sell in your fleshy parts, 7 years to replace every single cell in your bones. You are, literally, not the same person you were 7 years ago).

But I gave up asking "how did the game go?" or "is there anything I could have done better?" a long time ago. Why? Because my perspective as the person who wrote the adventure is not the same as the perspective of those who played it. The players do not know what I had originally planned, they don't necessarily know how I intended an NPC to act or look, and they certainly don't know what my expectations for the game were. Asking a generic question doesn't give me the information I need to improve.

So I've ended up shifting to three questions that do get me the information I need, not by being more direct but by eliciting the kind of discussion that tells me what worked in the game and what didn't.

This is, basically, "what did you think of the game?" but reworded in a way that is going to get the players talking immediately about the things that worked and didn't work for them. I'm not going to get a vague literary review of the plot or psychological analyses of the NPCs. I'm getting a rehash of the best and worst parts of the story.

"I liked the way this worked out ..."

"It was a little frustrating when this happened because I expected something else ..."

I can ask followup questions about comments to learn more about what they're saying, but mostly, at least with my group, I can just listen to them talk to each other about it.

Whatever else I ask after a game, I always ask this one when I want feedback. Not only is this discussion that comes out of this going to help me identify bumps in the story (stupid puzzles, unsatisfying conflict resolutions, a lack of information about certain situations), but it's going to tell me what the players expected from the story based on its opening scenes. This is important because if I set a tone that conflicts with the story I intend to tell, it's going to throw the players off and affect their perception of the game. Secondarily, it's going to give me a sense of the player's perception of the story pacing, and that perception is more important than the actual pacing.

This is actually less about the setting and more about my ability to share information in the game. Did I provide NPCs that are easily understood and who communicated their part well? Did the setting elements that ended up being important to the story have a clear part in the game world, or did we have to backtrack and throw in a few of those infamous "you don't know this, but your characters would" bits that are a clear sign of setting failure but that all of us have had to do at least once.

These three questions never fail to garner me useful information about the things that worked and didn't in my game. I've found them far more effective than just asking "what did you think?" They feed on player conversation, so I wouldn't use them over email. They're most effect when just taking 10-20 minutes to get a little discussion going at the end of a game, while the story is still fresh.

Will they work for you? Try them out. They're tailored toward the kind of information that helps me identify my own personal weaknesses, but they may work for you as well.

At the very worst, they might inspire you to use more leading questions to get to what you really want to know.