Lean QuickStart Guide_ The Simplified Beginner’s Guide to Lean - PDF Room

Defective Production
Defects equal cost and waste. Extra costs may be incurred through reworking,
scrap, production rescheduling, or additional labor costs. In some cases defects
can more than double the cost of production for a part. Defective production is
clearly a non-value-added activity; the cost to produce defective parts cannot be
passed on to the customer and must be considered a loss.
Overprocessing
Any time a piece or product receives more processing work than is absolutely
required by the customer, it is an overprocessing waste event. While processing
to the customer’s needs is certainly a value-added activity, customers will not
pay more for unnecessary work. Additionally, further processing could result in
the creation of new waste events such as wasteful motion, unnecessary waiting,
inventory and transportation costs, and the increased risk of defective
production.
Overprocessing presents a challenge to organizations that do not have a high
degree of visibility in the supply chain or have poorly established channels of
communication. That is to say that cooperation and coordination are often the
obvious remedies for overprocessing waste events. A high level of focus on the
customer’s needs and customer service, along with communication at all levels
of production, are effective methods of eliminating the root causes of
overprocessing. Later we discuss the pull production system, another method of
combating overprocessing and waste.
Waiting
In circumstances in which goods are not being processed, consumed, or in
transport, they are assigned the “waiting” status. Waiting is not a value-added
condition and represents a high degree of wasted time and effort that could be
better spent on value-added activities.
The elimination of waiting-related waste events is largely based on changes to
operations and logistics protocols. Effective plant loading and facility layout,
too, can highly impact the amount of time material spends waiting. An effective
production system moves goods quickly and efficiently in a steady flow; smart