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Let's agree on the following: just as performance everywhere can be illustrated with a bell curve, so does performance at work. In a bell curve we see that most participants saturate the middle of the curve. While it isn't nice to call those in the middle "mediocre", the term 'medius' comes from Latin and means middle. In other words, mediocrity is what people in the middle do.
Then, as performance increases to the right of the bell curve, we see very few participants. The higher individual performance is, the smaller the number of participants. Finally, to the left of the middle, we find the opposite. As performance drops, we see that there are fewer and fewer participants.
This matches my empirical experience. As an executive, I found that most people wanted to do a good job at work but couldn't for a reason. I saw that their performance was average when compared to the pool of available workers. Most displayed mediocrity.
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There are two main reasons why employees don't perform better. Either they do not have the knowledge or they don't want to use it. It's that simple.
While looking for the knowledge part, most hiring managers place way too much emphasis on identical job experience. They think that the only way to test for the needed technical insight is by matching the posting's title to the candidate's previous job titles. This is the wrong presumption. There are uniquely exceptional candidates who may presently lack some of the necessary knowledge who, as long as they have sufficient brain power, will have no difficulty with any technical aspect of the job. In no time, they will be up and running.
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As for identifying candidates who are willing to use their knowledge on their quest to the land of exceptional performance, the issue requires looking for signs of engagement-with-integrity, with emphasis on integrity. Let me tell you: you get smart people with very low integrity or ethical standards in your company and they will clean the company's bank account. Looking for brain power isn't enough. Any person who fails to have the qualities of engagement and integrity represents an eminent risk to the company. The least they can do is to sit on their hands when asked to take on additional responsibilities. Unfortunately, this is very common in all organizations. Still, it isn't as bad as it could be. Under the worst case scenario, the employee could absolutely sabotage the company. From corporate espionage, to destroying the relationship with key customers, to utter theft, are all possibilities.
Now I ask you, the HR expert, where in a resume or on your online application form do you have a way to identify exceptional candidates? Why is it that your application-filtering process takes the chance of getting rid of the many fantastic candidates who happen to fail some not relevant trait or experience? Yes, I am suggesting that you start by questioning the use of the job posting software you are currently using until you find a way to discern a candidate's technical knowledge, the need brain power and their engagement-with-integrity level. Don't be surprised if your hiring software of choice is letting you down. That would just be as expected; it would be mediocre.
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But guess what? Following this method is not easy. It requires work. It also forces hiring managers to make better decisions all the time.
No one has ever been fired for hiring an identical match to the job description. That's the safe thing to do. On the other hand, hiring a person from a different industry is scary to many. Not all people are up for the extra work or the pressure to make better decisions. Hiring managers, after all, are no different than the rest. Most are statistically mediocre.