Share with the class any experiences you have with process improvement methodologies such as lean, Six Sigma, total quality

Share with the class any experiences you have with process improvement methodologies such as lean, Six Sigma, total quality management, or others. Did you find it an effective process? How could it be improved? If you have no experience with process improvement, discuss how lean concepts could be incorporated where you work or used to work.
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ANTHONY:

Honestly, I don't have any direct experience with lean process improvement methodologies. I have worked with several companies that incorporate these methodologies into their operations and I have seen it really work, and I have also seen it cause some pretty serious issues, at least operationally. For the company's that I have seen it work for, they slowly implemented the changes into their processes and evaluated them with a wide variety of employees, from the bottom to the top, and changed those processes as necessary to achieve the desired results. 

For those that I have seen where incorporating a lean methodology into their process failed, the changes came fast without input from workers, from upper management and when there were failures, the workers were told to "make it work, or we'll find someone who will", or something along those lines. In those circumstances (just a couple), the implementation ultimately failed and the costs associated with implementing the program were a complete loss. In one company in particular that followed this implementation method, they ultimately failed so much, that they filed bankruptcy and the plant had to be idled, where it remains to this day.