Are personality tests accurate for hiring? Six beliefs that lead owners astray

It depends on the test and on what you do with it

A personality assessment built and documented for selection, chosen because it relates to the job, and used as one input alongside skills, structured interviews and references can make hiring decisions noticeably better than resumes and gut feel alone. The same assessment used as a pass-fail cutoff, or a tool built for team-building used to pick candidates, can make decisions worse while feeling more scientific. Accuracy is not a property of personality testing in general; it comes from the right tool used the right way.

I studied personality psychology in Texas A&M's industrial and organizational psychology program, and personality-based recruiting is what I do at Wayne Human Capital in Dallas. Owners bring me strong opinions about assessments in both directions. Some trust them too much, others dismiss them entirely. Here are the six beliefs I hear most and what I tell people about each one.

Belief one: any personality test will do

This is the most common and most costly mistake. Personality tools are built for different purposes. Some are designed for self-awareness or team-building, and they describe preferences without any claim to predict job performance. Using one of those to choose between candidates is like using a bathroom scale to measure height.

The best-known example is the Myers-Briggs Type Indicator. Its publisher, The Myers-Briggs Company, has said plainly that it does not condone using the MBTI for any sort of hiring or selection, because it was not devised for that purpose. If the people who make a tool say it does not belong in hiring, that settles the question.

A tool fit for selection comes with documentation: what it measures, how it was developed and what evidence links it to performance at work. Ask for that before you use anything, and be wary of any vendor who cannot provide it.

Belief two: candidates will just game it

Candidates do try to present themselves well, on assessments just as in interviews and on resumes. That is a real limitation, and it is one reason I never let an assessment stand on its own. Every source of information in hiring can be shaped by a motivated candidate. The question is whether adding the assessment gives you a more complete picture than you had without it.

In my experience it does, because it gives you something consistent to test in the interview. If a candidate's results suggest a strong preference for working alone and the role is constant collaboration, I ask for specific examples of tightly coordinated work and how it went. Patterns that hold up across the assessment, the structured interview and the references are the ones I trust. Patterns that appear in only one place get a closer look.

It also helps to be open with candidates about why you use an assessment. When people understand that there are no right answers and that the goal is to find a role where they will do well, most answer more naturally. A candidate who is a poor fit for the role usually has as much to lose from a mis-hire as you do.

Belief three: the score tells you whether to hire

No personality assessment should make a hiring decision by itself, and a good consultant will tell you so. Results describe tendencies, not certainties. People adapt to roles, learn new habits and behave differently in different environments. Treating a score as a verdict ignores all of that.

Automatic cutoffs also create problems that are easy to miss. The U.S. Equal Employment Opportunity Commission's guidance on employment tests explains that a neutral test which disproportionately screens out people in a protected group can be challenged unless it is job-related, and that employers should validate tests for the jobs they are used for. A rigid cutoff applied without that groundwork raises both the decision risk and the legal risk. Use results to decide what to explore, not whom to reject.

A better approach is to treat each result as a question. If a report suggests a finalist may struggle with ambiguity, the right response is to ask how they handled a time when priorities kept shifting, then check the answer with a reference. Sometimes the concern is confirmed. Often the candidate has already learned to manage that tendency, and you would have rejected a strong hire on a number.

Belief four: personality testing in hiring is legally off-limits

Some owners avoid assessments because they assume testing is illegal or too risky for a small company. That is not what the federal guidance says. The EEOC's guidance on employment tests lists personality tests among the selection tools employers use and focuses on using them without discrimination and in a way that relates to the job.

There is one important line to know. The EEOC's guidance on pre-employment medical examinations says a psychological examination is medical if it provides evidence that would lead to identifying a mental disorder, and employers generally cannot require medical examinations before a conditional job offer. A test designed and used to measure only things such as honesty, tastes and habits is not medical. Tools built to diagnose mental health conditions do not belong in pre-offer hiring. I go deeper into these rules in using personality tests in hiring yourself, and into the headcount thresholds in the hiring laws that apply as a Texas company grows. For your specific situation, talk to an employment attorney.

Belief five: every job has one ideal personality

Owners sometimes want a single target profile: the perfect salesperson, the perfect office manager. Real teams do not work that way. The same role can be done well by people with different styles, and what succeeds depends on the team around the person, the manager and the stage the company is in.

That is why I build a role profile from your team rather than from a generic template. A sales role in a fast, informal company calls for different strengths than the same title in a careful, process-driven one. And a team where everyone shares the same profile has blind spots. Part of reading assessment data well is spotting the strengths your team lacks, which is the idea behind weighing culture fit against skills and experience.

Chasing one ideal profile also shrinks your candidate pool for no good reason. You end up passing on people who would have done the job well in their own way, and you hire people who match a template but not your team.

Belief six: a company our size is too small to benefit

Large employers have used structured selection for a long time, and some owners assume it is only worth the effort at that scale. I see it the other way around. In a company of ten to one hundred people, each hire is a meaningful share of the team. One poor fit in a small department changes the mood of the whole room, pulls a manager's attention for months and can cost you a good employee who gets tired of covering.

Small companies also tend to hire less often, which means less practice and fewer chances to learn from mistakes. A structured process with good assessment data partly makes up for that missing experience. The investment does not have to be large; for many owners, a hiring workshop for their managers is enough to change how they select.

The one thing a small company should not do is copy a large employer's process wholesale. You do not need layers of screening. You need a defined role profile, a documented tool, consistent interviews and someone who can read the results sensibly.

What accuracy looks like in a real hire

In practice, an accurate process is one where several kinds of evidence point the same way. Here is how I combine them so no single source carries more weight than it deserves.

If your recent hires keep going wrong despite good intentions, the problem is rarely that you lacked a test. It is usually that the process had no consistent way to weigh what you saw, which I describe in why the resume keeps producing the wrong hire.

• A role profile built from the team the person will join, written before any candidate is seen.
• A real skills floor checked through work history, work samples or skills tests.
• A documented personality and cognitive assessment given to every finalist the same way.
• Structured interviews designed around what the assessments raise.
• Reference calls with former managers about specific behavior.
• A written recommendation that names strengths, fit and the risks to manage.

Getting a straight answer about your own process

If you already use an assessment, or are considering one, I am glad to look at what you have and tell you honestly whether it is the right tool and whether it is being used well. Sometimes the fix is small, such as moving the assessment to a different stage or using it to plan questions instead of rank people. Sometimes the tool needs replacing.

And sometimes the honest answer is that the assessment is fine and the problem sits elsewhere, in a role profile that was never written, interviews that vary from candidate to candidate, or a team environment that is pushing good hires out. I would rather tell you that than sell you a new tool.

I work with companies across Dallas–Fort Worth in person and with others remotely. Bring the tool you use, how you use it and a short account of your last few hires, and we can work out what would make the biggest difference.

Questions people ask me