Most everyone knows what reliability means in its precise sense, and we can refer to definitions most anywhere which are all consistent. But I know that some of us who work in the reliability fields often struggle explaining what the field is about, and what is included or excluded in it.
I have a proposed definition for the reliability field: the study, management, and reduction of the variability in supply to meet uncontrolled demand.
Now some people will react to that definition to say something like “I am a reliability engineer, but I don’t do all that.” But I think what they do will fit within that definition.
Others will say that definition is rather broad, and doesn’t address components and systems, which is really what reliability as a profession addresses. But I suggest those components and systems, indeed even those systems-of-systems, networks, and other such creations are all supplying some function, capability, or are themselves being supplied for such, and therefore the focus is really on the supply. That supply is impacted by our creations, thus we often turn toward those creations to address the real issue, which is variability in supply.
As the managing editor for IEEE Transactions on Reliability, and as a consultant in the networks and systems reliability field (among other fields I support), I think I’ll start testing this definition, or similar forms of the idea, with people outside the engineering and scientific fields, to see how well it conveys what the profession is really about. I suspect it will work better than the definitions we often point to in dictionaries and textbooks.