Giving “someone” (probably stakeholders) an impression or perception that the project is big and requires detailed step by step development by frequent updates by different team members on status that the project is still ongoing (not dead) and on schedule but sometimes “proper” methodology doesn’t guarantee the final product is what it is imagined at the first place.
Edit: For me, it just a tool to make someone happy so it is easier for them to answer to the stakeholders. I am referring to project manager or salesperson.