The short answer
Add follow-up questions when they help the reader advance from the primary answer to a related decision. Keep them in the same article when they depend on the same explanation. Create a separate page only when the new task needs its own substantial answer and examples.
A worked example
A fictional guide to choosing an image format can answer whether transparency matters in a short section. A detailed tutorial on cropping coordinates has a different task and a working tool, so it deserves its own destination. Publishing separate pages for 'PNG or WebP?' and 'WebP versus PNG?' would likely repeat the same comparison.
A practical checklist
- Write the primary question and the next decision a reader may face. Identify whether the follow-up adds a new workflow or simply clarifies the existing answer.
- Use a subsection for dependent clarifications and a related link for genuinely different tasks. Make the relationship visible in the link wording.
- Review new pages against the library before publication. Merge overlapping explanations instead of manufacturing variations to increase the article count.
What to avoid
Avoid promising that covering a certain number of follow-ups will trigger answer-engine visibility. The editorial goal is a complete reader journey, not a formula. Keep the library focused enough that a visitor can find the right article without navigating several near-duplicates.
A useful follow-up
How do I decide between a subsection and a new post?
Choose a subsection for the same task; choose a new post when the reader needs a meaningfully different answer and workflow.