The conductivity of carbon black can easily be overlooked with material. It is a relative natural assumptin to figure that plastic is non-conductive. The addition of any color typically adds a certain amount of carbon that increases its conductivity.
"sufficient perseverance must occur to resolve all the root causes" is huge! Too many times processing engineers/design engineers/ etc...stop at almost good enough and fight quality for the rest of the time. I know this because I've done it. You just get tired of fighting it.
And I certainly understand your statement, "just because the problem didn’t totally go away doesn’t mean you didn’t fix a root-cause source of the problem." But...if I have several problems; in this instance, 3 and I fix 2, I have to ask myself, will everyone be ok with that? If not, I've often times had to come with a dollar vs time figure to show that I'm justified in continuing to try to solve the problem OR its not worth it to go on.
Good points, plasticmaster. This was a particularly strong Sherlock Ohms posting. The detail of the process outlined here reveals the complexity of tracking down problems and the difficulty of determining when you've reached the point of diminishing returns.
The first Tacoma Narrows Bridge was a Washington State suspension bridge that opened in 1940 and spanned the Tacoma Narrows strait of Puget Sound between Tacoma and the Kitsap Peninsula. It opened to traffic on July 1, 1940, and dramatically collapsed into Puget Sound on November 7, just four months after it opened.
Noting that we now live in an era of “confusion and ill-conceived stuff,” Ammunition design studio founder Robert Brunner, speaking at Gigaom Roadmap, said that by adding connectivity to everything and its mother, we aren't necessarily doing ourselves any favors, with many ‘things’ just fine in their unconnected state.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.