On the Area Definitions tab, in the navigation pane, click the Edit Global Stage Lifecycle button: 
The Edit Global State Lifecycle dialog box appears.
Select the stage for the transition you want to delete in the Lifecycle Model.
Select the transition(s) you want to delete in the Transitions area and click the Delete Transition button: 
You will be prompted with a dialog box asking you to confirm the deletion.
Click OK to delete the transition(s). Any off normal stages that no longer have any transitions to or from them will also be removed.