The Myers-Briggs is a rough indicator of temperament also, the error rate about one out of four assessments being not correct. In theory, temperament does not change. Because you get different assessments at different times, indicates more about your character, than it does your temperament. We don't know how temperament is formed, but it appears very early in childhood. In reality, since temperament is not measurable and only indirectly observed by watching one's behavior over a long period of time, determining temperament can be an ongoing process.
Individuals vary in the degree in their ability to observe themselves.
Also temperament is a pre-disposition towards a particular configuration of habits. We all have the capability to behave in ways not common to our strongest pre-disposition. That is, one can view your temperament in the metaphor of the fingers on your hand. Your pinky indicates your short suit, behaving in a way that is not very strong, because you tend not to practice those behaviors you are not pre-disposed to prefer. Aren't you putting them in boxes, as form of stereotyping.