“You Don’t Manage What You Don’t Measure” … But Do You Really Manage What You Measure?
Mazri, Chabane

How to Cite

Mazri C., 2021, “You Don’t Manage What You Don’t Measure” … But Do You Really Manage What You Measure?, Chemical Engineering Transactions, 86, 361-366.


The imperious need to measure safety performances through indicators is now a well-established tradition in the process safety community. You don’t improve what you don’t measure has consequently been the mantra that drove important efforts of the community towards not only building reliable lagging representations of safety evolutions but also designing leading indicators providing decision makers with anticipation abilities.
Taking a step back in order to gaining perspective allows us to understand the origin and foundations of this situation. P.Drucker’s “If you can’t measure it, you can’t manage it” seems to be the original starting point that indeed has spread throughout the management community in times where quality management was promising zero default products and conformity to standards believed as the key to successful management. However, management science has moved away towards far more modest precepts thanks to large efforts dedicated to observing real life decision making and organizations appropriation of management tools.
Consequently, it is required for the safety community to deconstruct this precept and explore its validity given process safety specificities. This paper is a contribution to this effort. We will discuss accordingly this precept through two complementary angles. The first (measuring but not managing) questions the extent to which measuring paves the road for good management. This first angle provides the reader with the key traps separating measurement from management. The second angle (managing without measuring) shed lights on successful management practices not necessarily relying on anterior measurement.
One should not throw the baby with the bathwater. This work is not be understood as a proposal to put aside or discredit safety measurement efforts which remain necessary. It however invites safety managers to put these approaches in perspective and question their validity scope so to make the best out of them without being imprisoned by their limits or sometimes, misleading character.