The ISTJ personality type is not considered rare, but it is not as common as some other types. ISTJ stands for Introverted, Sensing, Thinking, and Judging. It is one of the 16 Myers-Briggs Type Indicator (MBTI) personality types.

ISTJs are known for their practicality, reliability, and strong sense of duty. They are often described as responsible, organized, and detail-oriented individuals. They prefer to focus on facts and concrete information rather than abstract ideas. ISTJs are often seen as traditionalists who value stability and order.

One reason why ISTJs may be perceived as rare is that they tend to be more reserved and introverted. They prefer to spend time alone or with a small group of close friends rather than engaging in large social gatherings. This can make them less visible or less likely to stand out in social situations.

ISTJs are also known for their strong work ethic and dedication to their responsibilities. They are often seen as reliable and dependable employees who take their work seriously. They prefer to follow established rules and procedures and may struggle with change or uncertainty.

In relationships, ISTJs are loyal and committed partners. They value stability and security and are often seen as reliable and trustworthy. However, they may struggle with expressing their emotions or being open to new experiences, which can sometimes lead to challenges in their relationships.

Overall, while ISTJs are not considered rare, their reserved nature and preference for stability may make them less visible or less likely to stand out in certain social settings. However, their practicality, reliability, and strong sense of duty make them valuable contributors in many areas of life.