The nature of work analysis concerns evaluating whether any sub-process or process step is value-adding or non-value-adding. This level of analysis takes your initial value process evaluation down to the next level of detail. Just as you looked at the overall process for waste and redundancy, you will apply this same thinking to each sub-process or even individual process step. Each step that has been determined to be non-value added by nature of work analysis may then be further categorized into:
- In-house failures: These are procedures or procedure steps involving rework to correct errors or defects in the process. They will almost always be identified by the prefix "re," as in re-work, re-test, repeat.
- Peripheral failures: These are errors or defects that involve rework but are not discovered within the process. These errors are found and identified by the customer and are considered actual process failures.
- Control or inspection failures: These procedures aim to correct errors and involve rechecking, verification, and corrections. Though they may be necessary in some instances, they are considered non-value-added steps.
- Delays or wait times: These are the most commonly seen non-value-adding steps. This will be evident when there is a build-up at process points of inventory, work in progress (WIP), or bottlenecks.
- Lead times: The procedures that involve set up and "getting ready" to begin processes. These can be nonvalue added when they are excessively or unnecessarily long, and this extra time causes the process end time to fail to meet customer expectations.
- Movement failures: This failure involves unnecessary movement times to gather raw materials or movement of finished product to the customer. It is usually considered a non-value-added activity.
