Some surveys are simple, just a few questions.  It's easy to set them up as one record per questionnaire.  Some surveys are simple, but long.  With scores or even hundreds of questions it doesn't make sense to define a record with that many fields.  The audit/inspection example presents one approach to handling large numbers of questions.  Some surveys require not only many questions, but also intelligent presentation of the questions depending on previous answers.  Thus, if we're taking a patient survey we may ask whether the patient is pregnant, but only if the patient is a woman.