A quiz funnel is useful when answers materially change the recommendation, segment or next step.
Have a real reason for each question
Every question should improve relevance, qualification or personalization.
Keep the promise clear
Tell users what they will receive after completing the quiz.
Design the result
The outcome should be useful on its own and naturally connect to the next step.
Avoid fake personalization
Do not present generic results as highly individualized recommendations when the answers did not actually affect the result.