A person's so-called personality is the instinctive way of responding to different situations, essentially shaped by early life experiences, an unexamined default setting. This setting allowed you to survive in your early environment, but as the environment changes, it becomes ineffective and gradually out of touch with reality. Personality is part of a person's sense of self, and transforming one's personality instinctively feels like a betrayal of the self, so most people lack the awareness and motivation to actively change some obviously outdated settings in their core. Personality transformation is like a controlled demolition of oneself. The process can be quite painful. But as you accumulate more experiences and your threshold for enduring pain reaches a certain height, once you start to taste the benefits, you will begin to actively conduct targeted controlled demolitions of your various outdated default settings.