Lean priciples

The five-step thought process for guiding the implementation of lean techniques is easy to remember, but not always easy to achieve:
1. Specify value from the standpoint of the end customer by product family. 
2. Identify all the steps in the value stream for each product family, eliminating whenever possible those steps that do not create value. 
3. Make the value-creating steps occur in tight sequence so the product will flow smoothly toward the customer. 
4. As flow is introduced, let customers pull value from the next upstream activity. 
5. As value is specified, value streams are identified, wasted steps are removed, and flow and pull are introduced, begin the process again and continue it until a state of perfection is reached in which perfect value is created with no waste.