In kaizen, a common goal is to optimize an assembly line or departmental process by streamlining value added tasks and eliminating wasteful tasks. Sometime we end up transferring the wasteful activities to other departments, suppliers, employees off the line and, in some cases, even customers.
This is not a principle of lean manufacturing. The waste still exists within the value chain therefore a cost still exists. Somebody still pays. Yes, throughput may be improved and cost lowered yet it still exists.
Focus on eliminating the waste and not passing the burden to others.