To me, the key elements in a project are navigation and transparency. Alongside content and expertise, being aware of the status of subtasks is vital for managing larger projects. A visual solution map (for instance, in SupplyChainDesign) can be incredibly useful in our endeavors; it’s inexpensive yet makes a substantial impact - see this example:

Here is my experience: In my career, I have seen waterfall projects completed successfully time and time again because they were planned through from the start. Each phase is clearly defined and there is little room for ambiguity or misunderstanding. Of course, there are also challenges, but a structured approach with fixed milestones provides security and creates trust within the team. For me, it is the way to manage projects stably and efficiently. Agile may be useful in certain situations, but for complex supply chain projects I prefer the tried and tested waterfall approach.