4 Reasons Why I Stopped Using MBTI to Understand My Personality

(And why science suggest you do the same)

You’ve heard about MBTI, don’t you? So probably after some online test or reading the personality descriptions now you know what type you are. INFJ or INTP maybe? Knowing it, living became a bit easier, don’t you think? Now it’s easier to understand and accept yourself. Maybe it’s even easier to interact with other people?

For a long time that was my thinking as well. But is it really such simple? Is putting yourself and others into one of the 16 personality types enough to understand people?

My story with MBTI

I began using MBTI after reading a 200 pages book about the concept. At first, it sounded very good. 4 dimensions, giving 16 types of personalities, clear descriptions of each of them. The entire concept based on Carl G. Jung's work — even I didn’t know much about his thoughts, it was proving MBIT is somehow more science-based.

Just after reading the descriptions, I knew it for 100% — I’m INFJ type! What’s more, the book says it’s the rarest of all personalities — isn’t it clear evidence of my uniqueness? For sure — that’s about me!

And what’s more — the web says that there are some very well-known and influential INFJ leaders as well — Mohandas Gandhi, Plato, or even Jung himself! So that’s another piece of evidence — I’m in an exclusive club of INFJ’s. For sure this thought gave me more confidence.

So after such a valuable experience, I started to talk about MBTI to other people. Of course, I had no official tests of psychometric instruments, so I was just showing personality descriptions from the book or web pages. And I was trying to persuade my family members or my friends that for sure they’ll find a type which is 100% their own.

Sometimes they were defining their type in less than 3 minutes. Sometimes they’re just agreeing with my proposition of it — as thanks to being INFJ, my view of it was for sure very clear. But sometimes something strange was happening — they couldn’t find the right type.

I remember well a long talk with my good friend about the MBTI. She’s always been very self-conscious so I was sure she’ll find her right type very fast. But you know what? She couldn’t make it at all! In the end, she considered herself as a person somewhere between ISFP and ENFJ…, nothing more. What a surprise!

Sometime after this talk finally I had a chance to take part in a professional MBTI assessment, with an accredited trainer. I was excited because now I had to have 100% confidence in my INFJ type.

Everything was good until we’ve got the final results of an assessment. I was totally confused - it showed that I’m not INFJ but rather… INTJ. Yes, I know, it’s just one letter but you know what? I was really attached to thinking of being such a person as Gandhi was!

When we were discussing the results right after the assessment, the trainer said to me that my personality type is not only about the result of the assessment but also about how do I feel about it. In other words — if I’m not comfortable with the idea that I’m an INTJ maybe in reality I’m an INFJ. It really didn’t help me a lot, but rather confused me more.

After a few months at my university, I had another chance to take part in an MBTI assessment. So I did. But now, even without a conscious goal, I was focused on answering right. Which I mean: answering in such a way to get an INFJ result. And so I did it. Now it showed that I’m 100% INFJ. But it didn’t help me to rid myself of my confusion regarding the entire MBTI concept. In reality, my doubts have grown.

Am I really an INFJ type? Do people for sure fit 100% in just one of the 16 types? Is it a proven, science-based concept? And how the hell do all these web pages know what is the MBTI type of people living hundreds or more years ago?

That said, I started to search through the web. And you know what? I was surprised by how easy this search was.

There are exactly 4 reasons you should stop using MBTI.

Reason #1 — Pigeonholing and discriminating majority

MBTI is based on pairs of opposite characteristics (dichotomies), assigning each person completing the test to one of the opposite characteristics. Unfortunately, the MBTI dichotomy-based approach is controversial because it assumes that we are eg. either introverted or extroverted - thus locking out to people who are more in the middle of the scale than at the ends of the scale.

Meanwhile, most studies show that traits are normally distributed in society. This means that approx. 15% of the population is at the introverted end, approx. 15% at the extroverted end, and as much as approx. 70% near the middle of the scale.

Thus, the dichotomy-based approach discriminates against the majority of society and is not a correct description of their actual personality traits for these people. To put it simply — the approach used in the MBTI is misleading as both extreme extroverts and those who scored only 51% extroverted are classified as “E”, which can lead to simply false conclusions about themselves.

Reason #2 — Fluctuating test scores

The scientific value of a test depends, among other things, on how independent is it. That is, how reproducible results does it produces when used under constant conditions. Translating this into MBTI — if someone is identified as an ENTP type, for example, then we should be sure that after five weeks of taking the test, it will still show that they have the same type.

Unfortunately, the scientifically measured reliability of the MBTI test turns out to be low. According to the researchers, for about 50% of respondents, when they complete the MBTI test again after 5 weeks, it indicates a different type of personality. Yet the assumption that after just 35 days we have half the chance that our personality will change in relation to just one trait - is absurd.

In addition to the dichotomies issue (discussed above), it can be also explained by the fact that the results indicated in the test require honesty. Meanwhile, MBTI has no mechanisms to reduce excessive or socially expected responses. As a result, there is a risk that the test result can be easily manipulated — either unconsciously (e.g. under the influence of emotions) or consciously (e.g. to match the type of personality to the job position, during a recruitment process).

Reason #3 — Promises overgrowing the real value

The publisher of the MBTI assessment advertises it as a tool to get to know yourself better, strengthen social skills, improve relationships with family, friends, and colleagues, and make better life choices. But that’s not all — for the MBTI organization, it is supposed to be a tool to change the organizational culture, create leadership development programs and increase recruitment success. In short: the promises are huge.

However, these are the advantages described not by CPP (MBTI owner), but by derivatives to MBTI, the tests visible on the Web are the most controversial. One of them is advertised i.a. as a tool for learning about personality-tailored learning styles, matching job profiles, or as a basis for assessing compatibility with a potential life partner.

Meanwhile, critics point out that there is no evidence of the effectiveness of using MBTI to measure job performance at individual positions or to use the test as part of career counseling.

The feeling of the excess of promises over the actual value delivered completes the frequent use of MBTI on the Internet to assign personality types to celebrities or historical figures. Understandably — without the need (or rather the ability) to complete the test… Sometimes even on the same web page, the same man has different personality types (eg Ronald Reagan as ESFP or ENFJ). On one of the pages, even the personality of Jesus Christ is defined.

Reason #4 — Not separating introversion from neuroticism

According to the remarks of Hans Eysenck, the MBTI scale, and more specifically its dichotomy concerning extraversion and introversion, contains a significant correlation with a group of personality traits called neuroticism in the Big Five model.

According to the research results provided by Eysenck, it was shown that introversion measured by MBTI negatively correlates, i. a., with domination, aggression, and self-confidence, and positively — eg. with readiness to give advice. According to the researcher, the fact that the MBTI does not separate introversion from neuroticism is the biggest drawback of the test.

Alternatives to MBTI

On Google.com, under the slogan ‘Personality test’, MBTI or connected concepts are still the most popular personality assessments. But at the same time, the Google Scholar search engine indicates 150 times more items about Big Five than the MBTI.

So is it really about choosing between an easier to understand, popular MBTI concept and a more complex, science-based Big Five model? My answer is: yes, it is.

In the end, to give you something even more valuable than my complaints about MBTI, I have a proposition. Just read about the Big Five and how was it created. Check if it’s right for you. And if it’s so — just go through a science-based assessment.

Here you’ll find an example of an online one (3–8 minutes to complete), based on an IPIP Big-Five Factor Markers. Another, more popular version of the Big Five assessments is NEO Five-Factor Inventory (NEO FFI), but for this one, you’ll need to pay. You can find it eg. here.