For the past 40 years I’ve been working with hiring managers, recruiters and candidates on all types of jobs from camp counselors to senior executives. Part of this has been tracking the results of their hiring decisions including what happens to people who didn’t get hired for a dumb reason at company A, but did get hired at company B for the right reasons.

Given this perspective, here are 15 things I’ve found that absolutely don’t predict on-the-job success. Despite the obvious, companies, recruiters and hiring managers still use these factors to make critical yes/no hiring decisions.

  1. First impressions. Not everyone with a good first impression is a top performer and not everyone without one, or who is initially nervous, is a bottom dweller. Even in sales, the only common predictor of future success is a track record of exceptional sales results.
  2. Gut feelings. A Rational Way to Make a Gut Decision was the subtitle of my first book. The idea was to gather as much performance-based evidence as you could to validate your gut decision. Trusting your gut too soon is a recipe for being wrong 50% of time.
  3. Generic competencies. Competency models are a fraud! Converting generic competencies into measurable results isn’t. For example, for strong communication skills say, “Present monthly update reports to the executive team.” Unless you can measure a competency from a job-related standpoint like this, it has little value.
  4. Personality-based assessment tests. Stop using DiSC, MBTI, PI and BEST to screen out candidates. At best these are confirming indicators, not predictive, and at worst, they’re preferences, not competencies. Despite this, the BEST test, however, is the best of the lot.
  5. Introverted vs. Extroverted. The reason extroverted people are statistically more successful is that there are more of them. On a per capita basis there is little difference. Whether you’re introverted or extroverted is far less important than hard work, reliability and a no excuse attitude. This is true even in sales.
  6. Being on time for an interview. Give me a break. One could argue that only hungry job seekers are always on time. Although I would expect the late person to apologize since this is a sign of good team skills.
  7. Being prepared. Give me another break. One could argue that the hungry over prepare. However, the person being made an offer better be thoroughly prepared.
  8. Telling you they want the job. This depends on when they say it. If it’s before he/she knows the job, I wouldn’t hire the person. It means the candidate is non-discriminating and desperate. After he/she has full knowledge, it’s important but the reasons why are more important.
  9. Being employed or not. At least they’ll be on time if they’re not (see point 5). However, if someone is unemployed, I’d expect the person to be spending a lot of time on personal improvement, not taking time off.
  10. Being an active candidate. Most hiring managers value passive candidates and referrals over active candidates. This might be a good sourcing idea since there are more of them, but it’s not a predictor of job success.
  11. Using a behavioral interview. One or two examples of past behavior do not predict future performance. Past performance doing comparable work in a comparable situation with a comparable manager does predict future performance. A continuous track record of growth in past behavior doing comparable work predicts future behavior doing similar work.
  12. Cultural fit. Unless defined exactly, this is another term for “hiring in your own image,” which is PC for anti-diversity. Success working with different people in different situations for different managers is a better predictor of cultural fit.
  13. Academic credentials. Being smart enough to do the work is a strong predictor of success. However, those who are too smart often overthink a problem and those who aren’t smart enough under-think it.
  14. Level of experience. The bottom half is filled with lots of experienced people who achieve average results. The best people – those in the top half -get promoted faster, are assigned bigger projects ahead of their peers and get more done in less time. As a result, they have less experience.
  15. Strong statistical correlation. High correlation between two factors doesn’t mean one caused the other. For example, it’s likely that a behavioral interview is more accurate since it’s structured, and, as a result, it increases objectivity. If so, any means to increase objectivity will be just as effective.

Given all of these hiring myths and non-predictors, some might ask how to eliminate people who apply but aren’t qualified. I’d suggest sending everyone who applies an email describing a major project involved in the job. Then ask those interested in the job to prove their ability by describing in 1-2 paragraphs their most comparable past accomplishment. The weak will deselect themselves. This is called the two-step apply process and, by itself, it overcomes most of the problems described above. (Here’s the legal validation for this.)

Hiring stronger people starts by stopping doing these 15 things. Unfortunately, stopping doing the wrong things is more difficult than doing the right things.

Lou Adler (@LouA) is the CEO of The Adler Group, a consulting and training firm helping companies implement Performance-based Hiring. He’s also a regular columnist for Inc. Magazine and BusinessInsider. His latest book, The Essential Guide for Hiring & Getting Hired (Workbench, 2013), provides hands-on advice for job-seekers, hiring managers and recruiters on how to find the best job and hire the best people. His new video program provides job seekers inside secrets on what it takes to get a job in the hidden job market.