The universally-recognized abstract definition of productivity is the ratio of output to input.
Construction and other industries today have adopted a narrow subset of productivity and generalized it as “the” productivity. Construction productivity, as utilized today, is not a useful metric to rely on for monitoring project health, creating reliable cash flow and forecasts, deriving schedule durations, or evaluating claims.
The productivity methods currently utilized fail to consider that true productivity requires a complete set of “inputs” and a complete set of “outputs”, both additive and subtractive, and not just the number of widgets per labor unit. While input and output components vary from task to task, they are almost never as simple as the ratio of a single output to a single input.