Are you an ISFJ or an ESFP? Wait, don't answer that. Your Myers-Briggs personality type might not actually matter at all.

The 93-question test is the most widely used personality test in the world; some two million people answer the questions each year to find out which one of 16 personality types most closely fits them. But the two women who developed the test in 1945 had no formal training in psychology, and as a recent report by Vox explains, the test is essentially worthless.

As noted in the video above, our personalities don't fit neatly into classification boxes. As proof, one study found that 50 percent of participants received two different Myers-Briggs classifications when they took the test twice, five weeks apart.

And yet, while the solidity of Myers-Briggs has been tested and found faulty time and time again, many large corporations use the criteria to hire and organize employees.

So why then, does the test endure? Find out in Vox's video above.

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