Ask HN: What is the need for Jira status workflows?

In JIRA, you can configure workflows to control the movement of an issue's status. For instance, you can enforce a rule where an issue cannot move directly from "In Progress" to "Done" without first transitioning through an "In Review" stage.

Question: I never really understood the importance of this feature, do you have use cases where you've found this feature particularly helpful?

We're considering implementing similar workflow customization in Tegon, our open-source project management tool. What do you think? Is this feature needed?