This is one of my favourite charts.
Project waste and backflow It shows a project as a classic network of activities, annotated with green and red lines. The green lines represent forward flow – the natural progression of tasks we desire in a smoothly flowing project. By contrast, the red lines represent back flow – the rework required to handle defects, errors, ambiguities and poor project design. The red lines are a major source of project volatility.
Are you doing everything in your power to design and execute your project properly to eliminate the waste and back flow?