You can remove a process from a stage in your case type when it is no longer required.
In the explorer panel of Designer Studio, click Cases and then click the name of a case type.
On the Life cycle tab, hover over a process name in a stage.
Click the Delete icon.
Click Save.
The process is disassociated from the stage but the underlying flow is not deleted. You can reuse the process later, by adding it to a different stage or process within a stage.