One of the first steps an organization takes before planning and implementing DevOps is to map out the software development value stream to determine where DevOps will provide the best ROI. You can improve efficiencies throughout the entire software development lifecycle by automating the least efficient development tasks and reducing friction between teams.
The value stream concept predates DevOps methodology and is most closely associated with lean manufacturing. In a manufacturing environment, companies use value stream mapping to identify and eliminate waste, making the manufacturing process more efficient and reducing costs. For example, a widget company would trace and document every step it takes to make each widget in a flow chart. Using that data, they can identify and eliminate sources of bottlenecks in the process. Once one bottleneck is eliminated, value stream mapping shows where the next inefficiency is in the manufacturing process, and the company works to eliminate that.