Personality tests can be fun to take, but they can also be frustrating. They’re black and white. Most popular personality tests assume that people can be classified into distinct personality types. But, people don’t fit into neat boxes. Most people aren’t entirely introverted or entirely extroverted, for example.

But despite the fact that many of these tests rely on a flawed framework, they’re still widely used by employers of all sizes. It’s easy to see why: We want to be able to understand how people can work better together.

Myers-Briggs was developed in the 1940s, and there have been lots of advancements in the field of personality research since then. But the assessment, and ones like it, have staying power—especially in workplaces—because it feels like an easy way to match “types.”

However, the test has a low test/retest reliability, meaning if you take it again, you’re not necessarily going to get the same results as you did the first time. Other kinds of measures, like the Big 5 personality characteristics, are more stable across one’s lifespan and so are more reliable.