It happened about 15 years ago, but I remember it very clearly. My sensei, never one to mince words, shared his thoughts on the performance of the four teams. He grabbed a flipchart and scratched out a formula - one that I now call "waste elimination effectiveness."
The W.E.E. = identified waste X acknowledged waste X eliminated waste. It's cumulative, like rolled throughput yield (i.e., 80% X 60% X 65% = 31%). A low % in any of the factors is NOT good, multiple factors, disaster.
Some teams fared a lot better than others in the sensei's semi-quantitative assessment. I don't remember the scores. Not really important. What is important are the underlying principles and perspective. Here are some of my humble W.E.E. reflections.
The great Hiroyuki Hirano calls the practice of identifying waste "wastology." Pretty cool term. In my estimation, it's about 85% technical skill and 15% behavioral. In other words, with study, hard work , the right tools/techniques, and a lot of practice, you can learn how to identify waste. In order to drive the W.E.E.'s waste identification number, you also have to apply sufficient rigor and stamina.
Now, you can teach a person to identify waste, but you can't MAKE them acknowledge it (kind of like that horse and water thing). The willingness to acknowledge waste is primarily behavioral. I put this at a 10% technical and 90% behavioral "skill mix." A retributive culture and/or a lack of humility will minimize acknowledgment. Of course, lazy folk know that if they don't acknowledge the waste, then they won't be obligated to try to eliminate it ("Waste? What waste?").
...And even if people acknowledge the waste, you can't MAKE them eliminate it. Some just don't have the killer instinct. I see elimination as a 50%/50% split between technical and behavioral. A lack of bias for action or aggressiveness will limit waste elimination. Similarly, from a technical perspective, if the kaizener does not apply adequate countermeasures, and apply them against the real root cause(s), they're just spinning their wheels.
So, generating a high waste elimination effectiveness level is not easy...but, pretty much anything worth accomplishing isn't easy.