Reasonable reasons include:
1. getting married
2. being adopted (usually! but not if Cabal families are involved)
3. making your name easier to pronounce or spell or recognize - especially for actors/politicians, etc.
~ ~ ~ ~ ~ ~
and don’t forget:
4. Parents name a kid with a horrible name.
Example:
True story.... while in the hospital, a mom thought she heard a GORGEOUS word and and thought it would be a perfect name for her beautiful new baby girl:
Placenta.
...thought it would be a perfect name for her beautiful new baby girl:”
Placenta.
and there’s that old story where a certain Mrs. King saw the perfect name for her son as she was wheeled into the delivery room:
Nosmo