There’s a saying that you can’t manage what you don’t measure.
It’s true in the sense that sometimes its very hard to get a grip on reality and the progress that a project has made unless you institute mini and major milestones for project members to keep track of.
Personally, I do not like to have “mammoth” project milestones where they appear on the project progress chart week after week. It can get quite demoralising at times for the project members involved in that milestone task and it may also make it difficult to explain progress to higher management. When managing projects, it will be better to cut the mammoth milestones into mini milestones so it will be easier to track progress as will as improve morale.