dictionary

Efficiency and Efficacy: Meaning and Differences

The terms efficacy and efficiency, often used interchangeably as synonyms, actually reflect two very distinct concepts.

Let's be clear about it.

Effectiveness indicates the ability to achieve the stated goal, while efficiency assesses the ability to do so using the minimum necessary resources.

Effectiveness and efficiency are very important concepts in the world of work and in general in the planning and control of any activity.

If two athletes aim to run the 100 meters in less than 10 seconds and succeed in their intent, they are both effective; between the two it will be more efficient the one that will have achieved the goal with the least expenditure of resources (time dedicated to training and costs for technical material, coach, nutritionist, integrators etc.).

The concept of effectiveness and efficiency is also expressed in the image below, where the circle indicates the starting point and the star the one of arrival, while the line of conjunction between the two symbols represents the set of actions taken to reach the goal (finish line or point of arrival). In the first case we note a particular tortuosity of the action, which reflects an expenditure of huge resources to cross the finish line; consequently, the action is effective but not at all efficient. In the second case, instead, the target is centered with the minimum use of energy: the action taken to reach the goal is therefore particularly efficient.

We are very effective and very efficient when we reach the maximum by spending the minimum.