The objectives for each question should be specified. When you start with an objective, you should use questions that will address those objectives.
Simple questions can fail to address objectives as easily as complex questions.
Various answers may require probes. High school, IBM, Bell Helicopter, U of M, etc. A codebook should address the intention for each question. This can serve as a guide for interviewers, or if you work alone, it can clarify your thoughts. Snowballing questions is possible with open ended questions.