Is it actually that? I'm pretty sure that the term comes out of the Toyota Production System, in which kaizen, or continuous improvement, is the heart of the pr

Is it actually that? I'm pretty sure that the term comes out of the Toyota Production System, in which kaizen, or continuous improvement, is the heart of the process. Given that the Ishikawa diagram also comes out of post-war Japan's industrial process quality improvement community, I would be very surprised if Totota didn't make use of Ishikawa diagrams in practice.