In order to walk away from the requirements interview with good requirements, the questions asked need to be properly thought out and strike the right balance.  Here are a few key characteristics that help the analyst produce a set of quality requirement interview questions.

1. Some questions need to focus on the as-is process. 
2. Other questions should ask about the major pain points in the process or what might be missing.
3. Questions should be a balance of open-ended and close-ended questions.  Close ended questions may not yield as much breadth of understanding, but too many open ended questions can make it difficult for the interviewee to give that analyst structured or relevant feedback (i.e., avoid too many questions that start with “Why”). 
4. Ensure that the questions are not leading questions which imply an answer; this can negatively influence the information that the analyst receives.
5. Keep it brief. The primary list of questions should be only 7-10 high level.
6. Each primary question may have a number of more specific follow up questions.