Turning Mistakes Into Marvels


Jared Evans, Professional Instructor and Lean Process Coach, MasterControl, Salt Lake City, UT, USA


Jidoka, Poka-Yoke, Quality Management, Defect Elimination





We all know the pains of making a mistake. It can be torturous to look back with no clock ticking, all the possible solutions to a problem plainly laid out, and the results of those solutions much clearer than they were at the time. In today’s market, characterized by ever-shrinking budgets, increasing operational complexity, and easier access for competitors, mistakes make it even harder to achieve and maintain success in an already overly competitive environment.

With its goal of achieving the highest quality at the lowest cost with the shortest lead time, quality management is hard. It can feel like a constant contradiction – at times seeming like you must give up one important quality element to attain another. It can also feel like one big balancing act between different commitments to customers, whether those commitments are delivery dates, quantity levels, quality levels, or something else. Add the unpredictable nature of mistakes to the already complex equation, and the challenge facing quality management increases exponentially.

Unfortunately, to err is human, and therefore inevitable. A study conducted by the U.S. military and aerospace programs showed that humans are often the least reliable components of complex manufacturing systems. In fact, the study found that at best, humans cause one error in every 10,000 attempts.

But those inevitable mistakes don’t need to result in defects. While mistakes are bound to happen, achieving zero defects in your process is possible!

Your company may have already implemented a Statistical Process Control (SPC) program. This type of system reports the quantity of defects that you can realistically expect from a process – data that can be highly beneficial to your business. But knowing is only half the battle – it’s what you do with the information that counts. In addition to an SPC, why not introduce a process for proactively addressing the mistakes identified by your SPC system before they become defects that reach your customer?

This session will introduce two lean concepts that can help make this happen: jidoka, which is the combined ability of intelligent workers and machines to identify errors and take quick countermeasures to make a process defect free; and poka-yoke, which is the prevention of inadvertent errors.

Attendees will learn about the different types of inspection systems to support their poka-yoke program including judgment, informative, source, vertical, and horizontal systems, as well as three different categories that these systems use to detect deviations. The session will also share best practice actions to take when the system identifies a signal for warning or shut down. Finally, it will discuss how to implement jidoka and develop a long-term strategy to support a company’s overall lean strategy.