Because you changed the Leave Request Workflow, you must redeploy it to the K2 server. Deploying the workflow publishes it and makes the current version available to your users. You must redeploy a workflow each time you make any changes.
In this step, you deployed the Leave Request Workflow to the K2 server. The changes you made to the workflow are now ready for use! In the next step, you will edit the rules on the Leave Request Form to enable the Approver Comments control for the approving manager. (Remember, when you added the control to the item view, you made it read-only by default. Now you will enable it for the manager.)