Today ,personality testing is a multi billion dollars industry  ,used by individuals , schools , or companies .but none of these test ,including MBTI, the big five ,the DISC (assessment ), the process communication model and the enneagram . actually reveal  the truths about personality ,in fact ,it’s up for  debate whether the personality is stable measurable  features of an  individual at all . Part of the problems is the way of test are  constructed ,each is based on  different set of metrics  to define personality . the Myers-briggs focus on features like ,introversion ,extroversion  .to classify people into personality types , while  the big five scores participant on five different traits.  Most are self-reported ,mean the results  are based on question participant  answer about themselves ,so it’s easy to lie ,but even with the best intentions , objective self-evaluation  is tricky . enneagram 九型人格 traits  特性