Because I picked it when I was 15 and 1) was worried about privacy and 2) wanted a name that seemed “cooler” than my real name. XD I realized the no-name-change-required perk a bit later. Nowadays I use my real first name in a lot of situations, but I still use my pen name on published works and in my more professional online-only correspondence. I rarely include my real last name in any situation, for continued privacy reasons.
Fantasy/dystopian/sci-fi author. Mythology nerd. ENFP. Singer.