I have had a few usernames in the past (the most common being scienceman87, which I thought of in like a minute because "you can always change it later") but I was never really happy with it, and over the course of several years I would occasionally try to think of a username that i liked and could use everywhere, but I never could, partly because I tend to be picky about these kinds of things. So when discord did the whole username overhaul thingy, I knew this was the perfect opportunity and I'd probably never get a better one. To get around my indecision/pickiness, I established a few criteria that I could use to figure out if a username was good or not. It needed to be a max of 7 or 8 characters, ideally less (so it can fit in a Splatoon name along with a team tag), it needed to be unique (so that it isn't already taken on most sites and so it would be recognizable), and I needed to like it (because being stuck with a username I don't like is the problem I was trying to fix). After spending days brainstorming and not coming up with anything good, I finally resorted to trying random combinations of sounds. I started to get stuck on that too (true randomness is hard/impossible) I decided I'd think of existing words but change them. The first one to come to mind was "squid", because I play as an Inkling, and the most obvious change was to flip around the d to become a b. It sounds nice, is unique, and it just felt right (which is the only important part, really). It's only 5 characters, so there's plenty of room for whatever team tag I end up having, and it is also really easy to say. The only problem left was that it's so short that when I tried to use it as a username, it was already taken. So I had to think of a longer version. And since it sounded like "squid" I immediately started thinking of splatoon-related puns. And the song from the trailer came into my head and I knew I had to do it.
It's kind of like my history with weapons, where I went through a lot of different ones but eventually I found one that was just perfect. And I don't think I'll be changing my username anytime soon. (Although I'm not exactly sure why I decided to use underscores on squidboards and nowhere else.)