Some performance metrics may actually hurt what they measure

Charles Darwin. Photo by J. Cameron, 1869. (© Bettmann/CORBIS)
Charles Darwin. Photo by J. Cameron, 1869. (© Bettmann/CORBIS)


The use of the Bell Curve in performance evaluation incentivises self-centric behaviour over joint alignment towards organisational purpose, pitting colleagues against each other. Mankind's most meaningful achievements result from collaborative effort, rather than a lone genius

Who developed the theory of evolution? Who invented the telephone? What about the radio? Pretty obvious answers one would assume. Charles Darwin, Alexander Bell and Marconi respectively, right? Well, it’s not as straightforward as we might think.

Both Charles Darwin and fellow naturalist Alfred Wallace independently arrived at the theory of evolution. However, Darwin is historically credited with this theory even though the book, “The Origin of Species" which shot Darwin to prominence was published a year after the seminal paper on the theory of natural selection, which was jointly authored by Wallace and Darwin. Alexander Bell and Elisha Gray both developed the technology and filed patents for the telephone on exactly the same day; the 14th of February 1876. Bell was eventually allotted the patent after a bitter legal fight. And the inventor of the radio? Marconi or Tesla? Depends, because the two scientists developed the technology independently and history credits both of them, based on who wrote it.

While credit for countless inventions or discoveries may be debated, mankind’s most meaningful achievements result from collaborative effort of thousands of individuals and not a lone genius working single-handedly, however sensational the latter might sound. Development of the internet, vaccines, DNA sequencing, space exploration etc are all fields which may have public figure marquees as its heroes, but they represent the work of innumerable individuals who laid foundations, contributed and worked without the glory. On 20th July ’69 when the world watched Neil Armstrong’s moonwalk, they were witnessing efforts of 400,000 unsung people working on the Apollo program for eight years. That’s how many it took to put two men on the moon!

And while it is also true that like Armstrong, Steve Jobs, Newton, Einstein and Sir Tim Berners-Lee (The ‘father’ of internet), etc.— certain personalities capture the public’s imagination, significant accomplishments are the result of collaborative load sharing rather than the extraordinary performance of an individual gladiator. Sadly, that is often not the way several organisations manage their talent.

Most talent appraisal systems are reductive in nature and perhaps none as disabused as the Gaussian distribution, commonly known in corporates as the infamous Bell Curve. The theory propounds that while it may be impossible to predict the result of a single event, it is possible to predict the outcome of multiple events because most cluster into the ‘middle’ with a few deviating to either sides. This concept is easily illustrated using a slanting board that has several pins stuck out. If a single metal ball is rolled from the top to the bottom, its path and final resting place is erratic because the direction of the ball changes randomly each time it hits a pin and hence is unpredictable until settling on the bottom of the board. But, if a hundred metal balls are rolled from the top, then they will fall into the shape of a curve or a ‘bell’ at the bottom, with bulk of the balls bunching in the center and a few on either sides.

The Bell Curve’s interpretation in performance evaluation of employees is that, most will be average, some above and some below average. This simplistic abstraction makes the appraisal process relatively easier to execute. It is easy to measure the median and deviations on either side. The HR strategy is to keep the ‘average’ satisfied by matching inflation, delight the ones who are in the high end of the bell curve and chastise or fire those in the bottom. However, the problem is that human beings aren’t metal balls.

Implementation of a bell curve in an organisation usually incentivises self-centric behaviour rather than joint alignment towards the organisational purpose. Those judged as average know that they will probably remain average because even if they improve, they will still be rated average since everyone else is also improving. Rather than fighting to get into the top percentile of the bell curve, they are more likely to cling to their average position fearful of dropping further. Those in the lowest percentile are understandably terrified and start seeking other opportunities. Their focus shifts from the organizational mission to self-survival. Like leading race drivers, those in the top percentile, fiercely defend their positions to a point of fratricide, expecting and giving no quarter to their competitors, unlikely to take risks, offer help or share credit. By promoting self-aggrandisement, the bell curve often pits colleagues against each other internally, rather than focussing on external competitors. Deploying a self-catering divisive tool is hardly the strategy for organisational alignment or synergy.

The supreme irony of the Gaussian distribution is that while German Carl Friedrich Gauss (considered to be one of the most gifted mathematician of the 20th century), did indeed formalize and popularize the concept, it was based on the work of lesser-known French mathematicians Abraham de Moivre and Pierre-Simon Laplace among several others. A concept which was developed as a collaborative effort over decades, is ironically at times being used to disincentivize collaboration within organisations.

Raghu Raman is former CEO of the National Intelligence Grid, distinguished fellow at Observer Research Foundation and author of Everyman’s War.

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