Suppose that you go to bed tonight and sleep well. Sometime, in the middle of the night, while you are sleeping, a miracle happens and all the troubles that brought you here are resolved. When you wake up in the morning, what’s the first small sign you’d see that would make you think, “Well, something must have happened – the problem is gone!”
The miracle question doesn't ask you to describe the miracle itself; it asks you to identify the tangible signs that the miracle happened. Once (someone has identified) specific and vivid signs of progress... a second question is perhaps even more important. It's the Exception Question: "When was the last time you saw a little bit of the miracle, even for just a short time?"
There are exceptions to every problem and that those exceptions, once identified, can be carefully analyzed, like the game film of a sporting event. Let's replay that scene, where things were working for you. What was happening? How did you behave? That analysis can point directly toward a solution that is, by definition, workable. After all, it worked before.
Chip & Dan Heath, Switch