These desires appeared to be rooted in dissatisfaction. People wanted to become more extraverted if they weren’t happy with their sex lives, hobbies, or friendships. They wanted to become more conscientious if they were displeased with their finances or schoolwork. The findings reflect the social psychologist Roy Baumeister’s notion of “crystallization of discontent”: Once people begin to recognize larger patterns of shortcomings in their lives, he contends, they may reshuffle their core values and priorities to justify improving things.

Social roles matter, too. As someone becomes more invested in a job, they often become more conscientious; likewise, when someone becomes more invested in a long-term relationship, they tend to become more emotionally stable and have higher self-esteem. In fact, the more the commitment is part of a person’s identity in any context, the more it appears to cause personality change.

To help certain participants with their goals, the researchers randomly assigned half of the students to engage in a “goal-setting” intervention. In this condition, the researchers reminded the students of the traits they most wanted to change and asked them to come up with specific and concrete steps (e.g., “Call Andrew and ask him to lunch on Tuesday) and to generate “if … then” implementation plans (e.g., “If I feel stressed, then I will call my mom to talk about it”). The participants were also warned that very broad goals, such as “I want to be more self-disciplined and self-controlled,” were too vague to cause any lasting change.

Over the course of the semester, the student’s goals to change their extraversion, agreeableness, and emotional stability appeared to inspire actual growth in the desired direction. For example, people who said they wanted to be emotionally stable “more than they currently are” actually increased their emotional stability each month. What’s more, people who came up with concrete plans for reaching their goals showed much greater changes in extraversion, conscientiousness, and emotional stability than those in the control group. However, the intervention did not boost growth in agreeableness beyond merely wanting to be more agreeable.