Myers-Briggs is a standard personality testing tool that has been in widespread use for decades. There is nothing very scientific about it, but the virtue of an approach based on dichotomies, is that if you score high on a particular trait it is difficult to read the opposing trait as applying to you. It is not, as someone, suggested like a horoscope that can be read as applying to anyone; at least not unless you have a very meh, neither-one-thing-or-the-other type personality.
MBTI is certainly not an indicator of success in the work place, even if the snake oil human resources industry have latched onto it in that context. It might help you to identify which job you would enjoy, but not whether you would be any good at it. And results are completely falsifiable, which is a problem with its use in aptitude tests.
In any case most workplaces benefit from a range of personality types. As a manager I find an awareness of dichotomies helps to make best use of the strengths of my staff rather than tearing my hair out in frustration at their weaknesses. *keeps telling himself this*
