ISTJs (introverted, observant, thinking, and judging) are a respectful and serious personality type. It is no surprise that ISTJs are sometimes referred to as logisticians for they enjoy a rhythm to their lives and this helps them to feel most comfortable with a definite preference for following a particular pattern to completing tasks.
principles
ISTJs come across as pleasant and serious-minded. With a no-frills aesthetic and a no-nonsense approach to life, they don't often stand out in a crowd, but they don't shy away from the spotlight either. They respect the authority of others and prefer to follow the rules rather than make them, but they are not averse to taking charge to ensure sure tasks are completed the right way
• They have a preference for structure, rules, simplicity, and predictability
• They can focus on and remember small details
• Objectivity defines the their approach to situations
• They are known for their loyalty
strengths
openness to constructive criticism
ISTJs hold themselves to high standards and they enjoy challenging themselves to develop competencies. They don't need to prove themselves to anyone but themselves, so when someone gives them hints and tips for improvement, they are likely to take it as an opportunity to grow and eagerly tackle the new challenge rather than nurse hurt feelings.
loyalty
An ISTJ is well-known for surprising people with their loyalty. The ISTJs in your life may not say much, particularly on personal matters until you are very close friends, but may show up in moments you least expected to receive support from them. They have a tendency to consider any kind of social bond to be a serious commitment, whether with friends or family.
honesty and integrity
A deep commitment to authenticity is one of the hallmarks of the ISTJ personality. They will rarely break promises and ensure that any they do make can be kept. ISTJs are seen as honest individuals and do not immediately resort to lying, particularly over trivial matters.
diligent listening
ISTJs may appear quite expressionless when someone is speaking to them, but they are well-known for paying close attention to everything someone is saying. ISTJs take people's words at face value. When asked, they are often able to offer thoughtful advice based on a thorough and carefully-considered understanding of the situation.
weaknesses
inflexibility
ISTJs try not to make an assertion without first ensuring it's logical and based on proven facts. Once they've established that something is true and they've argued that point, they may be reluctant to consider other points of view, especially when opposing arguments are based on personal emotions or values rather than objective data, which conflicts with how other types view how the world should be.
limiting focus
ISTJs are motivated to get things done when the task before them is clear and the steps are laid out. At times to their detriment, they neglect to take the big picture into account and lose track of overall goals. With only a vague idea of where they need to end up and no path laid out, they may give up rather than rely on their own abilities to develop needed strategies.
lack of sensitivity for others
ISTJs are very good at setting their feelings aside in order to determine what is real, what is true, what is correct, and what is the proper course of action. They don't get their feelings hurt easily, so they may say and do things that are devastating to others without realising the impact. Because they don't observe their own emotional reactions very often, they may not register the feelings that arise in those with whom they interact.
social isolation
These types prefer to connect with others on an intellectual rather than emotional level. Sharing facts about a topic of special interest may feel quite meaningful, while the other party may have no idea, they've been involved in what the ISTJ felt was a deeply personal, even intimate conversation. ISTJs often stunned at the way people can breeze in and out of each other's lives. Their social needs are minimal, but they often go unmet.
friendships
ISTJs may have numerous acquaintances with whom they get along well, but there are usually only a few people they count as close friends. They place their trust carefully, believing that the people they associate with reflect who they are themselves.
Like any other relationship, friendship is a serious responsibility for an ISTJ. They will always make themselves available to a friend in need. They listen closely to what their friends tell them and can be counted upon to offer sound advice.