Take the “Why do we exist?” personality test …
The justification for this test was simple. Most of the personality tests that we take are based on the premise that by identifying “unseen” motivating factors, we can devise what drives an individual.
That’s a bit inhumane, though. We can decide/define who we are for ourselves; nobody really knows us better than we ourselves do … superficial traits are just those.

Therefore, one way to test for a “general” personality whilst still respecting the idea of the individual, is to roughly link us up with a famous thinker.
With this test, I first chose a series of philosophical – or more specifically – existential thinkers.
I made the range of answers to this question (implied by each philosopher) with a range of about 8 different subtypes; when I initially wrote the test, I used feedback from test takers to add to the personality types themselves and give them a real world feel.