Naming characters is one of those little details that can add a lot of color to a story. Without going into all the nuances of leaving them unnamed or giving them monikers based on license plates, here are some thoughts about what characters get called.
I once read a book where everybody had names like John, Martha, Bill and Mary. Now the author may have done this on purpose to underscore that they were common people (caught in an uncommon situation, of course). Personally I would have liked a couple of the names to be more distinctive, especially if they were tied to characters that needed to stand out.
In this age of multiculturalism, nomenclatures can also serve as gentle reminders of someone’s identity. When you read about Hakeem, you don’t confuse him with Seamus, much less with Kameko.
Focusing on a culture in history or aliens in the future might present names so uncommon that a cast of them can become difficult to sort out. Using names that are either descriptive or opposite can help designate which character is involved. Readers can remember that Victor is on a winning streak or Shorty is the tallest person in the room.
Keeping a name pronounceable can also be helpful. J. K. Rowling came up with seven creative ways to illustrate how Hermione is supposed to be said, but Syvwlch (unless you’re Welsh) could cause brain-lock for folks. Seamus might have to become Shamus, but that could only be if he leaves Scotland.
In the genre of romance you expect Prentice and Selena to fall in love, not Ralph and Betty. Nor would you believe an alien who told you his name is Skippy. Rusty sounds good on a cowboy (would he squeak when he walks instead of jingle?) but seems odd on a manicured businessman.
There are plenty of other factors that come into play, but I won’t be exhaustive here (it wears me out). Going beyond what’s in a What to Name the Baby book, however, can make calling your characters names more fun.
Just remember it’s considered bullying if you do that with real people….