Lean manufacturing is a term that describes a philosophy of optimizing time, resources and effort. The term "lean" was coined in the late 1980s, but, the basic goals date back to Benjamin Franklin.
Lean manufacturing methods result in products of increased quality because they impose a design and manufacturing process that identifies problems at the source. This technique impacts business, adding value.
The fact is that lean and quality are closely related.
Lean is not about speed, it is about value. If a customer understands and agrees that a process adds value (and will pay for it), it does not really matter how long the cycle time takes (assuming it is not preventing you from meeting their needs). Of course, it helps to look for ways to reduce overall cycle time if you can, but more often than not reducing cycle times are not anywhere close to being the biggest challenges to adding value. Instead, it is all of the “other” parts that make up lead time that need help: the wasted time and effort things spend waiting, being moved, being over processed and overproduced.
Quality is about value as well. All quality comes at a cost, whether it be good (prevention, appraisal) or poor (internal or external). Each one of those costs represent different levels of value to the customer, and to the parent organization. Customers will not pay you for defective product, nor will they pay more for good product because efficiencies are poor. The market determines what price can be charged for a product or service; it is organizational makeup and internal processes that determine cost.
In a true lean environment, anyone can halt production if they suspect there is a quality issue. Workers may shut down machines or even entire assembly lines if they notice a problem. While some people believe this is a costly process, the reality is that production workers are closest to the product and are often the first to notice when something goes awry. By respecting the worker’s insight and knowledge, the company saves time and money because they do not produce poor quality or out of spec goods. The process can be corrected quickly, before the company wastes a large amount of material or is forced to scrap or rework products to meet spec. A short line stoppage to investigate a potential quality issue is actually much less wasteful than fixing quality problems later in the process.
Keeping work spaces clean and well organized is another key aspect of lean that contributes to quality. One way is by ensuring that tools and components are stored in close proximity and a consistent and orderly manner. This increases efficiency and also prevents errors from mixing up parts that have a similar appearance but different characteristics. A clean work space reduces the likelihood of contamination or spoilage.
Following lean principles makes a company more efficient and helps to control costs, but, lean also contributes to product quality. Lean has catapulted many companies to higher profitability and increased market share.
Formalized problem solving methodology, tracked data and controls in manufacturing are essential to achieve lean success. Converting to a lean system utilizes the value of all and requires adjustments by everyone from the ground up within a company and its supply chains.