Page 348 - Design for Six Sigma for Service (Six SIGMA Operational Methods)

308 Chapter Ten

• Tools and equipment in the process
• Personnel participating in the process
• General resource goals of the process
• General resources available for the process
• Rules and regulations in the process
• Guidelines and techniques for operating the process
• Any exceptions to process guidelines, techniques, rules, or regulations

Process design uses PDLs as tools for documenting processes, and the final
design of a process should be documented using a PDL. The PDL acts as the
blueprint for the process in much the same way a drawing is typically used
as the blueprint for a new product design.

10.2.5 Process Performance Metrics
Any process design or improvement effort must ultimately confront the
questions, How good is good? and What does good mean? Good for a
process may mean, for example, low cost, high quality, or highly flexible.
Therefore, in designing and improving a process, it is essential that the
process management team establish exactly what good means to the organ-
ization. These will be the metrics for measuring the quality of the process.

Commonly used metrics include
• Process quality
• Process efficiency
• Process throughput
• Process flexibility and agility
• Process stability and robustness
• Human factors, ergonomics, and morale
• Process cost
Most organizations are interested in a mix of two or more of these metrics.
The typical organization will want its processes to provide excellent
quality, while yielding low cost and a satisfactory level of employee
morale. When two or more metrics are considered, especially if an
improvement in one metric may cause degradation in another, then relative-
importance weights must be supplied for making the tradeoffs between the
different metrics.

Before a process management project begins, there must be clear agreement
regarding which metrics will be considered and how interactions between
different metrics will affect the overall system performance.