alt Hacker News> In fact, management is full of numbers that a slightly-clever high school sophomore who’d paid attention in science classes could tell you are totally useless, because they were gathered all wrong. They mean nothing whatsoever. They’re just noise.
The whole point of SPC is to separate signal from noise. Pointing out that some change that everyone is obsessing over is well within the expected range is useful, it can head-off knee jerk reactions to phantom issues.
...assuming people want to know that the change is in the expected range. That's often not the case. People's careers are built on phantom improvements and being able to say that regular process issues were one-time occurrences.