Honestly I've been doing this for so long that the original reason got a bit hazy, but I'm pretty sure that back when I was joining fedi I still had some underlying self-esteem issues. Now it's just a habit of sorts. Plus, it's kind of fun to watch people's reactions to it? Sometimes they pat you, sometimes they fight you over it, sometimes they slide in your dm's with "mischievous" intent. I'm also sure people are so used to this now they'd think something's wrong if I stopped doing it.