As a young person I hated my first name; didn't want my middle name as that was my father's name; and people mis-spelled and mis-pronounced my surname so I was happier to be known by a nickname.
In my teens, I asked my mother why I was given such awful names. "Neither name was on our list of possible names. It was a complete surprise to me what your father registered you as on your birth certificate. As you know, it was a difficult birth and you weren't expected to survive. I think he gave you the name of his friend who was killed in the war. I suspect they were lovers. so he also gave you his own name. Maybe if you died your name would have honoured his lost friend and their relationship."
I still didn't like my name but was less determined to change it.
My mother was Scottish and my first university was in Aberdeen so I chose "Cameron Fraser" as my pen-name.
Now I am quite accepting of my names but still prefer to shorten my first name to Ray.