I have been dealing with the internet community for big chunk of my life, I have delt with all kinds of people in so many platforms.
One thing I noticed is the relation between the profile picture and the person's behavior and personality, ofcourse this might be so obvious because when you select your profile picture you try to pick something relatable to you.
So in this post I will share my expierence, linking the nature of the picture/image to what behavior I expect or have noticed.
1-Clear Personal Picture
If the profile picture is a picture of the person, with no fancy filters or anything, it is a clear sign he isn't joking about being in that platform, he is literally there for job, money, science or any serious topic.
he rarely insults, polite and "objective" in his talk.
2-Fancy or Unique Person or Fancy Personal Picture
Unlike first case, this one could be completely the opposite, but it highly depends on this "fancy" part, you may think of it as a metric, the more cringe the editing, the more cringe the person.
Also picking some cringe or useless person as profile picture may indcate the a low quality personality.
3-Nature Pictures
The most unexpected people, there is totally no rule here because anyone from serious to compete garbage may pick nature as profile picture, however it is noticable that people who simply pick a forest are calmer than those picking something like a galaxy.
4-Cartoon Drawings
I expect some monster to be behind that screen (In all aspects), espically if the image is from a cringe cartoon or not a TV cartoon, remember "pompompurin"? the guy behind breachforums?
5-Famous Anime
Guy must have wasted his life, now he tries to waste your life too, usually he has excessive knowledge over every useless topic on earth, he masters all useless parts of the internet, and has all sorts of useless skills.
The up side maybe the cringe fun you may get from such personalities, but at cost of being suprised that you can't offer to pay another month of rent, so becareful.
6-Not Famous Or Specific Anime
Guy would rather die than change his mind about anything, he is same as previous case, but less fun and more hardcoded on whatever mood he has.
7-Some famous actor
Straight up noob and unskilled at most aspects of life, he probably also wastes a lot of time much like case 5 and 6, but without mastering any useless thing.
8-Object, Abstract, Technical drawing, Text, etc...
This is where I fall at, my current profile picture as of the writing of this post is simply a method's technical drawing I made for a homework at university, beside not having anything else to put there, it also showcases an aspect about me (i.e being engineering student).
Same rule apply, the personality usually linked to the related topic of the picture, beside nature which we defined, stuff like a hardware component, medicine, city, etc.. indicates differnet things.
Just beaware if the picture is of something so off topic, it may indicate a crazy person.
9-Nice Animals
Birds, Cats, Horses, etc... indicates guy simply likes nature or enjoy wildlife, in serious situation it may mean he is naturalist or materialist, but in average case it means guy just wanted a profile picture.
10-Ugly or Nasty Animals
Pigs, Dogs, Donkeys, etc... Indicate the person is about to be crazy, if not already.
In serious case the guy is completely lost, reached the point of no return in being worse than Artificial intelligence in terms of intelligence.
Out of all categories this is a must stay away, from both friendship and business relations.
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Well this maybe a subjective topic, but the core idea stand, the choice of a profile picture is rarely (at least in my opinion) arbitrary and it reflects the profile holder's personality or state of mind.
Edit: Clearified 2 and 4, added 9 and 10
