Personality Tests in Executive Coaching

Personality tests are often recommended by executive coaches as structured tools useful for providing insights into a leader’s behavioural tendencies, communication style and decision-making approach. These assessments are purported to help outline key personality traits, offering a foundation for discussions between the coach and the executive. 

The results are often incorporated into coaching sessions to highlight areas such as leadership style, conflict management and team interaction. By apparently mapping personality patterns, coaches use these to tailor development plans to the executive’s unique profile. Personality tests are typically integrated early in the coaching process, intended to be reference points throughout the engagement to guide structured conversations and developmental focus.

Executive coaches frequently charge large fees for conducting such tests, as well as basing large proportions of their coaching sessions upon them – but how valid are they really? This article examines the usefulness of using personality tests in executive coaching. 

What Are Personality Tests?

Personality tests are simply structured tools designed to identify and categorise individual traits, preferences and patterns of behaviour. 

They are typically presented in the form of questionnaires, surveys or assessments, asking participants to respond to statements or scenarios. The results are used to generate profiles that are intended to reflect characteristics such as temperament, communication style or interpersonal tendencies. 

There are a wide range of personality tests available. Some assessments focus on broad personality dimensions while others emphasise workplace preferences, interpersonal styles or leadership tendencies. 

In a business context, four of the most widely used personality tests are:

• the Myers-Briggs Type Indicator (MBTI), which categorises individuals into personality types; 
• the DiSC assessment, which examines behavioural styles; 
• the Enneagram, which categorises individuals into nine distinct types; and
• the Big Five Personality Test, which measures five core dimensions of personality.

The Myers-Briggs Type Indicator

The Myers-Briggs Type Indicator (MBTI) categorises individuals into 16 distinct personality types. It is based on the work of Carl Jung’s theory of psychological types and was developed by Isabel Briggs Myers and Katharine Cook Briggs. 

The MBTI uses a structured questionnaire to identify preferences across four dichotomies: 

• Extraversion (E) or Introversion (I), which reflects where individuals focus their attention and gain energy; 
• Sensing (S) or Intuition (N), which indicates how information is perceived; 
• Thinking (T) or Feeling (F), which highlights decision-making preferences; and 
• Judging (J) or Perceiving (P), which illustrates approaches to structure and lifestyle.

By combining one preference from each of the four dichotomies, the MBTI produces a four-letter type code, such as ENTJ or ISFP, representing a unique personality profile. 

Each of the 16 personality types is associated with characteristic ways of processing information, communicating, and interacting with the external world. 

The MBTI is administered through a questionnaire consisting of a series of multiple-choice or forced-choice questions, with results presented in a detailed report outlining an individual’s type. 

The DiSC Assessment

The DiSC assessment categorises behavioural traits into four primary dimensions: Dominance (D), Influence (I), Steadiness (S), and Conscientiousness (C). Developed from the theories of psychologist William Moulton Marston, the model provides a structured framework for describing how individuals tend to behave in various situations.

• ‘Dominance’ is associated with a preference for control, decisiveness and directness;
• ‘Influence’ focuses on social interaction, persuasion and enthusiasm;
• ‘Steadiness’ emphasises cooperation, consistency and a calm approach; and
• ‘Conscientiousness’ highlights precision, structure and attention to rules and standards.

The DiSC assessment is administered through a self-report questionnaire, where individuals respond to a series of statements reflecting behavioural preferences. Responses are then analysed to generate a personalised profile that identifies the individual’s primary and secondary tendencies within the four dimensions.

Results are typically presented in a report that outlines the person’s dominant style, as well as how the combination of traits shapes communication and interaction patterns. The DiSC framework is available in multiple versions, tailored for different contexts such as leadership, management and workplace collaboration.

The Enneagram Test

The Enneagram categorises individuals into nine distinct types, each representing a particular set of core motivations, thought patterns and behavioural tendencies. Originating from historical traditions and later adapted into modern psychology, the model is structured around a nine-pointed diagram, with each point corresponding to one of the personality types.

The nine Enneagram types are typically referred to by number, though each also carries a descriptive label. These include: 

• Type One, often associated with principles and responsibility; 
• Type Two, centred on helpfulness and connection; 
• Type Three, characterized by achievement and adaptability; 
• Type Four, focused on individuality and self-expression; 
• Type Five, oriented toward analysis and knowledge; 
• Type Six, defined by loyalty and preparedness; 
• Type Seven, marked by enthusiasm and variety; 
• Type Eight, associated with assertiveness and leadership; and 
• Type Nine, reflecting harmony and receptiveness.

Each type is also connected to two adjacent types, known as ‘wings’, which can influence how the primary type is expressed. In addition, the Enneagram framework includes lines that illustrate patterns of movement between types under conditions of growth or stress. 

Assessments based on the Enneagram typically use questionnaires to identify an individual’s dominant type and related traits.

The Big Five Personality Test

The Big Five, also known as the Five-Factor Model of personality, is a framework that describes personality through five broad dimensions. These dimensions are Openness to Experience, Conscientiousness, Extraversion, Agreeableness, and Neuroticism. The model was developed through decades of psychological research and is structured to capture the major traits that consistently emerge in studies of human behaviour.

• ‘Openness to Experience’ refers to imagination, curiosity and a preference for novelty or variety;
• ‘Conscientiousness’ reflects organisation, dependability and a structured approach to tasks;
• ‘Extraversion’ encompasses sociability, assertiveness and energy directed toward external environments;
• ‘Agreeableness’ relates to cooperation, empathy and interpersonal sensitivity; and
• ‘Neuroticism’ represents tendencies toward emotional variability, stress sensitivity and self-reflection.

The Big Five is typically measured through standardised questionnaires in which individuals rate their agreement with a series of statements. Results are presented as scores on each of the five dimensions, rather than categorical types, providing a profile that shows where an individual falls on the continuum of each trait. 

Problems Inherent in All Personality Tests

1 – The Information You Choose to Submit Decides the Results

Personality tests are structured around self-reported data, which means the information produced by the test is entirely dependent on the information provided by the individual completing it.

These assessments typically include questions or statements designed to measure how often a person experiences certain feelings, emotions or behaviours. For example, participants may be asked to indicate how frequently they feel emotions such as anger or excitement, or whether they tend to identify faults in others. The accuracy of the results is directly linked to the responses chosen by the individual.

Because the process is based on self-assessment, both intentional and unintentional influences can shape the outcome. Some individuals may deliberately adjust their answers to create a certain impression, such as emphasising positive qualities or minimising traits they view as less desirable. Others may unintentionally affect their results by misjudging their own behaviours, misinterpreting the wording of questions or lacking full awareness of how they typically respond in different situations. 

In either case, the information gathered through the test reflects the individual’s perception of themselves. The outcome, therefore, is reliant on the degree of accuracy, consistency and self-awareness reflected in the responses provided.

Learn how a simple, practical shift in mindset produces radically improved outcomes in our article ‘How Attribution Drives Success’.

2 – The Information Submitted is only a ‘Snapshot’ in Time

Personality tests capture information based on self-assessment at a specific point in time. As such, the results represent only a ‘snapshot’ of an individual’s traits and behaviours. 

An individual’s current emotional state, physical state or anticipated future may influence perceptions of their own behaviours, tendencies or reactions, as well as how they are actually answering the questionnaire or survey, which in turn shapes the information recorded by the test. 

For example, if someone has a headache and is tired, or has a lot of work to get through and is distracted, they may not be concentrating properly on the questions and answering them correctly. If someone has had a very stressful and worrying week, they may respond to questions with a heavier emphasis on those aspects of emotions than they would usually. If someone has something they are really looking forward to coming up soon, they may be experiencing a change in their behaviour from their ‘baseline’. 

Personality tests do not distinguish between temporary conditions and underlying traits – they simply use the responses given. A single assessment therefore provides only a limited view, capturing the individual’s self-perception at a particular point in time rather than a complete representation of their personality. 

3 – Personality Is Complex and Situational

Personality exists on a spectrum, with individuals displaying a diverse range of traits, tendencies and behaviours which interact in complex ways and are varyingly dominant or subordinate depending on the situation. Personality assessments aim to categorise and describe these traits, but no single test can capture the full range of nuances that define an individual. 

Many personality tests are also designed around particular frameworks that emphasise certain traits over others. For example, the Myers-Briggs Type Indicator (MBTI) focuses on positive aspects of personality, while aspects such as neuroticism or low conscientiousness are not addressed. The structure and framing of these assessments can influence the types of traits that are recorded and emphasised, with certain tendencies highlighted whilst others are omitted.

Many tests additionally use generalised language in their results, providing descriptions that are broad enough to apply to a wide audience. Statements included in such assessments often highlight common human tendencies, which can resonate with many people, regardless of their specific personality.

Accuracy Issues with Specific Tests

In addition to these general problems, all personality tests are not created equal when it comes to scientific rigour and accuracy of results. Even the most popular and ‘reliable’ of personality tests struggle to stand up to real scrutiny.

The Myers-Briggs Type Indicator

The Myers-Briggs Type Indicator (MBTI) is one of the most widely used personality assessments in business contexts. While the MBTI has gained popularity for its accessibility and structured framework, its scientific accuracy has been the subject of extensive discussion within the psychological community.

Research indicates that the MBTI demonstrates limited reliability over time. Many individuals who retake the assessment after a short period receive different type results. Additionally, the MBTI’s categorical approach divides individuals into distinct types rather than measuring traits on a continuum, which contrasts with the continuous nature of most personality characteristics observed in empirical psychology.

The psychometric validity of the MBTI is also debated. While some studies show correlations between type preferences and certain behaviours, the predictive power of MBTI results for job performance, leadership effectiveness or other professional outcomes is limited. Curiously, despite these limitations, the MBTI remains widely used as a tool in the business context regardless of its lack of scientifically precise measurement of personality.

The DiSC Assessment

The scientific accuracy of the DiSC personality assessment has been the subject of ongoing debate within the field of psychology. While the assessment is widely used in business and organisational contexts, it has faced substantial criticism regarding its theoretical foundation, empirical support and measurement reliability.

The DiSC model is based on the early 20th-century theories of William Moulton Marston. Critics argue that these foundational concepts have not been updated to align with contemporary advances in personality psychology, which are grounded in extensive empirical research. As a result, the theoretical basis of DiSC is often considered outdated and lacking alignment with modern scientific standards.

Empirical support for the DiSC assessment outside of internal validation studies is limited. It was not originally developed through rigorous, independent scientific research, and critics point out that the evidence supporting its predictive validity (the ability to forecast future behaviours or performance outcomes) is weak. In addition, questions have been raised regarding reliability, with some studies indicating that test-retest results can vary significantly, suggesting inconsistency in the measurement over time.

The Enneagram Test

The Enneagram personality test is widely used in coaching contexts, but it is not considered scientifically accurate by the mainstream psychological community. The test lacks the empirical evidence, rigorous validation and standardised testing required for recognition as a scientifically supported assessment, leading many experts to classify it as pseudoscience. The Enneagram’s descriptive framework and theoretical origins limit its application as a reliable or precise tool for assessing personality in evidence-based settings.

One major concern is the lack of empirical evidence. There are very few comprehensive, peer-reviewed studies supporting the Enneagram’s ability to accurately classify individuals into distinct personality types. Its system has not undergone the systematic testing typical of modern psychological instruments. Additionally, the descriptions associated with each of the nine types are often broad, subjective and general in nature, resembling statements that could apply to many individuals. This vagueness makes the Enneagram difficult to validate scientifically.

The test’s origins also contribute to the scepticism surrounding it. Rooted partly in mystical and gnostic traditions, the theoretical foundation of the Enneagram is considered questionable by many researchers. 

For these reasons, the Enneagram is generally dismissed by personality psychologists as lacking the reliability, validity and empirical grounding required for scientific acceptance.

The Big Five Personality Test

Of all the personality tests, the Big Five Personality Test has the most scientific foundation and empirical support. Unlike many other personality assessments, the Big Five is grounded in decades of research, including factor-analytic studies of language and behaviour, making it one of the most validated frameworks for understanding human personality. However, it too has its issues.

The Big Five demonstrates comparably high reliability across multiple measures. Internal consistency for the five factors is consistently strong, and test-retest studies also show that scores are stable over time, particularly in adulthood.

Construct validity has also been established through correlations with other well-validated personality measures, while predictive validity is supported by extensive research linking Big Five traits to real-world outcomes. The model’s dimensional approach, rather than categorical labelling, allows for more nuanced representation of personality traits across a continuum, aligning with contemporary psychological understanding of human behaviour.

However, even The Big Five is not without its limitations and critics. Cultural bias and universality concerns have been raised. The Big Five was primarily developed and validated within Western, individualistic cultures, and research in non-Western populations has shown inconsistencies. This suggests that the model and associated assessments may not be universally applicable or equally valid across diverse cultural contexts.

Another limitation is that while the model effectively describes broad personality traits, it offers limited explanatory or predictive power. It does not account for the underlying causal mechanisms driving behaviour and has a restricted capacity to predict specific actions in particular situations. Additionally, the Big Five is not an all-encompassing model. Its focus on traits may overlook integrative aspects of personality, such as the organisation and interaction of different characteristics. 

Finally, The Big Five also carries the problems inherent to all personality tests – those of relying entirely on self-reported data at a specific point in time, with a limited ability to accurately reflect the full nuances and situational influences on personality. 

In Conclusion – The Usefulness of Personality Tests in Executive Coaching

Personality tests are frequently used in executive coaching with the intent of providing insights into behaviour, traits and interpersonal tendencies. However, a closer examination reveals significant limitations that call into question their usefulness in professional development contexts. 

Instruments such as the Myers-Briggs Type Indicator (MBTI), DiSC, Enneagram and even the Big Five Personality Test, while popular, have substantial constraints that reduce their practical value for executive coaching.

The MBTI and DiSC have been criticised for outdated theoretical foundations and limited empirical support, while the Enneagram is largely considered pseudoscientific due to its lack of rigorous validation. Even the Big Five, though more scientifically grounded, cannot fully account for cultural differences, causal mechanisms of behaviour or the nuances of individual personality and situational influence, and it relies heavily on generalised, time-limited self-reports.

Given these limitations, personality tests may offer at best a superficial or generic overview rather than meaningful, actionable insights. They most often produce broad, ambiguous or overly generalised descriptors, and they generally lack predictive validity for specific behaviours or leadership outcomes. 

In executive coaching, where precise understanding and targeted development strategies are essential, reliance on these assessments risks misinterpretation and overgeneralisation. Consequently, while often marketed as valuable tools, personality tests have limited practical utility in the executive coaching context and should not be considered reliable instruments for driving leadership development or executive decision-making.

To find out how to adapt to different personalities for better communication and results, see our article ‘4 Top Tips for Doing Business with Different Personalities’. To discover more about how to encourage the best from people, read our article ‘Developing High Performers’. To utilise an effective technique for creating outstanding results, explore our article ‘Flow State for Peak Performance’. To explore issues around company culture, see our article ‘How to Create a Great Company Culture’.

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