If under 60% who start finish, something is wrong. Diagnose by step.
Drop on question 1-3
The intro promised "5 minutes" but the first questions feel like research grade. Soften the openers. Maybe lead with the easiest, most pleasant question.
Drop mid-questionnaire
A single question is killing it. Look at the per-question dropout rate — there's usually one. Often: it asks for data they don't have at hand, or it feels intrusive ("how much revenue did you book last quarter?").
Drop at result page email gate
You're asking for too much before showing the result. Either reveal partial result first, then ask for email — or trust the score is good enough that they'll give email to see it.
Mobile abandonment
Check completion by device. If mobile drops faster, your questions might be too long for thumb-typing. Add shorter answer options or single-tap multiple choice.