The following factors have an impact here:
Placement on the website - from clearly visible areas to placement as advertising
Incentivizing users to participate: from a simple Call to action, up to a contest. Like you can see it here in an example: https://magazine.pinpoll.com/en/from-0-to-30000-leads-kagiso-media-shows-how/
The visual Design: from a simple design up to Custom Design via CSS for adaption to the CI
Content of the voting: we were able to determine that users usually answer 12 questions in average. That's why we suggest to use 10 questions maximum for a Poll, Quiz or Personality Test.
Traffic on the website: from few organic views per day up to millionfold views, which get generated through f.e. a paid Social Media campaign.