This is just my personal thoughts & musings on personality theory.
This bar of colour represents all the personalities and people in the world as they are. What are these colours? We're not blind (well not everyone)... there's obviously differences between them. How many colours do you see? Maybe we should give them names. If you can't tell that there's a difference between red and green then maybe you're colour blind - or personality blind or whatever.
Personality typing is trying to give names and mapping out this spectrum of personalities. Apparently there;s 7 types of colours!
Then someone comes along with an alternative way to map out the personalities and draw lines in different places. (is there 6 now?)
Then are super simple systems... 2 types, 4 types... etc.. I can go on (primary colours, secondary, complementary etc) we can talk very deeply about personalities here can't we? (CMYK/RGB Colour breakups)... and it can get super, super heavy once you reach colour profiles for the super colour nerds.
Then there's debates over which colour system is best or accurate.
There are the archetypes who fall neatly in the middle of the spectrum divides, but there are people on the edges of the personality types... neither red, orange… Neither blood orange nor mango... that throws off everyone. There are some that are like… You must be either a red or an orange. There are some that are like, "If I'm not red or orange or even blood orange, If I'm #FF8D00, then what am I?" Then the answer is, well, you're a mix of red and blood orange? You're definitely a warm type though. You're 42% Red and 43.543% Blood Orange.
Then there are those that are like "Well F* giving names to colours! I'm out! Everyone here is toxic! Just sticking to hexadecimal! It's more accurate!" - Then there are those that still see the value in giving colours names. Then we have to keep giving disclaimers like "The primary colour system is just a tool to help you understand where you are on the spectrum, or which area. It doesn't tell you your exact hexadecimal, or your colour exact CMYK/RGBbreakup."
So what's the value of knowing your colour/personality type? Apart from appreciating that there are different colours & personalities and valuing what they bring to the spectrum, I think it's to help you be more self-aware of things you maybe unaware about, so that you can consider improving it, rather than playing out your tendencies - "Well, it's who I am... it's my tribe, no changing me." as if your type gives you permission to act poorly in your particular way - whether it's being overly aloof, impractical, selfish, people pleasing, an A*hole, stuck up, callous, cold, obnoxious, narrow-minded, inconsiderate - whatever.
And guess what... there's actually more ways to self improve than through personality typing alone. Personality typing doesn't cover everything. Like attachment theories, neurology, ethics, skills, beliefs, philosophy, behavioural psychology, parenting styles, psychology. psychiatry... etc.
But out of all these, personality seems to be one of the most fun and
colourful ones to talk about

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TL;DR / MAIN POINT
There have been many personality models that attempt to map out human personality by grouping people with similar traits together. However, in attempting to do so, there are inevitably people who aren't sure which group they belong to because they share traits of both groups fairly evenly which can frustrate those on the fringes of an archetype.