As Peter De Jong and Insoo Kim Berg explain their book Interviewing for solutions, when coaches or therapists ask clients how they will know their problems will be solved, they often describe a final result, a finish line as it were. They describe a situation in which lots of things will be better. When they describe such a final result they may become aware of the contrast between that good situation and their current not-so-good situation, which may demotivate them. What coaches can do in these types of situations is to ask the first-sign-of-improvement- question, which goes something like this: "What will be the first small sign that will tell you that things are starting to move in the right direction?" This type of question usually helps clients to notice small positive changes (a.k.a. micro progression) which usually is very motivating.
Also read: 10 questions for the solution-focused coach