Forum Discussion
Ghost link
I referred to the Question Feedback option in the Design tab.
If this option is set to "None," the feedback layers are turned off for this question. If there is even one slide after the quiz slide, when you hit the "Submit" button, the Storyline will assume you want to proceed and will forward you to the next slide, regardless of whether you have other layers to show in place of the default feedback layers.
Check this example: I have 10 blank slides (no objects, no triggers, no default navigation buttons) and one quiz question with no submit button and no feedback layers. The quiz slide is still pointing to the next slide. You should not worry about as long as you have other triggers and objects in place that make your interactions work as intended.