Lean’s focus on waste may be its defining element. To reduce waste, it must be identified, understood for what it is, and then eliminated through process change. Time is a major emphasis. Engineers want to eliminate wasted time and time that does not add value. They want to make process changes that reduce operation time.
Lean’s waste lens is most effective when focused on repetitive, transactional work. The process is studied, judgments are made on value-adding vs. non-value-adding activities, and then good thinking is applied to eliminate those activities that customers won’t pay for.
On the production floor, processes are well-defined and repeated frequently. Flows are linear, so there’s little uncertainty about what to do when material arrives. Tasks are simplified to reduce reliance on documentation and mental memory. (Lean does take advantage of muscle memory, however.) Through continuous improvement, wasted motion is reduced and output per unit time increases. In the end, there’s little question people on the production floor work hard, and it’s good that the length of the workday is clearly defined and constant.
Lean is respectful of people, and engineers take great care to fit the work to the person. With the regularity of the production floor, a mismatch in capability or capacity is visually apparent almost immediately. Work piles up in front of the overloaded workstation, and everyone knows there’s a process problem. In record time, resources are added, or work content is rebalanced, or waste is designed out. The system works wonderfully.
Lean is now regularly applied outside the production floor. In theory, it works the same way. The work is studied, judgment is made about what adds value and what doesn’t, and wasted time is eliminated through process change. It does work outside the production floor, but it works differently.
Nonproduction work flows (i.e., back-office processes) are far more complex than those on the shop floor. They require much more judgment and have much more variation in the work content. Multiple demand streams are not bound by work-in-process limits. (Too many calls in the queue don’t stop other customers from calling.)
Lean theory has a simplistic answer: Straighten out the process flows, homogenize the work content, reduce judgment, and standardize the output. All great ideas, but they don’t necessarily apply to the back office. These are people-based processes with people-based inputs and people-based outputs. In fact, nuance, judgment and a personal touch are what make these processes successful. No checklist can effectively handle a customer complaint; no standard work is flexible enough to handle unpredictable situations; and customers respond very poorly to a WIP cap. When applied to these people systems in a production system way, lean eliminates waste along with the flexibility that makes these systems effective.
With these nonproduction systems, lean’s rules about capacity and work balance are not respected. In a people system, when there’s a pile of work on someone’s desk and he’s not meeting takt time, resources are not added in record time, the workload is not rebalanced, and waste is not designed out. Even worse, because process flows are so complex, the pile isn’t noticed at all. If it is noticed, management tends to think it’s a people problem not a process problem.
Lean is most effective when used with repetitive, transactional processes with highly constrained inputs and streamlined process flows. People systems aren’t like that. While it’s helpful to take waste out of our people systems, it’s far more important to increase flexibility and give the people within the systems more autonomy and authority to use their judgment.