The name is usually one of the first things we learn about a character.
Like it or not, readers are inclined to react differently to a character called Chloe or Saffron than to a Mildred or Ethel. First impressions, in fiction as in real life, can be startlingly accurate or blisteringly unfair. They're also inclined to be hard to shift. So characters' names need to be chosen with some care.
I want my characters to have names that suit them; a part of the word picture that paints them. I'm also constrained by the times in which I set my works. I don't believe there were many Chantelles, or Tiffannie-Krystals, in Victorian New Zealand.
Quite a few names from Victorian times are still in current or near-current use, and I've tended to choose from those for my younger characters. Names that sound old-fashioned (at least in 21st century New Zealand) are fine for older characters.
On checking the most popular names given to babies in New Zealand in 2008, I find I've used five out of the top ten names for girls, and seven of the top ten boys' names. Boys' names tend to keep to the traditional a little more, but babies of both sexes are given more of those traditional names than was the case in the 1950s-60s.
The lists, with the ones I've used marked by an asterisk:
Girls - *Sophie, Olivia, Ella, Isabella, *Charlotte, *Lily, *Emma, *Emily, Jessica, Grace.
Boys - *Jack, *James, *William, *Samuel, Joshua, Riley, *Liam, Oliver, *Benjamin, *Daniel.