Character names are a bugbear for me. When a character pops up in my mind I usually get to see (roughly) what they look like and can even hear their voice when they speak. Unfortunately, they never tell me their name. It's me that has to decide on that.
Rather than interrupt the flow of my writing, I tend to give this little thought. Jim is a favourite name of mine. Most male characters start up being Jim or John or Tim or Toby. This, however has to be sorted out otherwise the reader can become very confused. Then they get irritated, then they throw my book in the bin.
Of course, in real life we meet lots of people with the same name. That doesn't work in fiction. Even names beginning with the same letter should be avoided in order to reduce the possibility of confusing the reader. On the page, words with similar lengths starting with the same letter often get confused. It's because of our brains always looking for shorthand ways of doing things. There's lots of examples, here's one:
Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it dseno’t mtaetr in waht oerdr the ltteres in a wrod are, the olny iproamtnt tihng is taht the frsit and lsat ltteer be in the rghit pclae.. The rset can be a taotl mses and you can sitll raed it whotuit a pboerlm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.
That's why I can have lots of friends called Peter and never get them confused but can't have similar character names in my novels or the reader will.
So, if I've got a Jim, I have to avoid John and James and Jacob and Jack and Joshua.
This is a pain in the backside for me. And I could do without any more pain in that region, believe me.
I like short names. Like Jenny and Kat. Like Toby and Alex. Like Mac and Mick. Oh dear. Mac and Mick. They're both in Limited Liability! I suppose there has to be an exception to every rule.
Don't let this put you off buying Limited Liability when it comes out next month. I don't think you'll mistake one of these guys for the other. Let me know if you do get confused, though, and I'll have a word with my editor.