Approving user stories
Development sometimes begins before collaborators involved with the issue have agreed on the requirements. Approvals are used to inform collaborators that you agree with the requirements and that work is ready to begin on a particular user story.
Using Approvals alongside Questions is a great way to communicate with collaborators to clarify requirements.
The Ready button shows how many people have approved the requirements, hovering over the button reveals a dialog containing the users that have interacted with approvals.
Once a user has approved the issue, their avatar will appear in the dialog with a green tick badge. Should they remove their approval, the avatar will persist in the dialog but without the green badge until the user re-approves.
You can ask questions using the Question button, doing so will remove your approval on the issue until you re-approve it after your Question has been resolved.
Its possible to perform JQL queries from within JIRA to filter issues by Ready and Question count, see JQL Search.