Parents think about nicknames in advance because they are sort of inevitable for many names. Little Michael's parents might have never called him anything but Michael and asked his teachers to only call him Michael, but as soon as he's old enough to form friendships with other kids, one of them is going to call him a shortened version of his name on the playground, and that's probably going to stick. If little Michael's parents hate the nicknames Mikey and Mickey, they can call him Mike occasionally, and the kids on the playground will probably end up calling him Mike too. Also, Mickey and Mikey are cute names for a boy, but they have a sweet, silly, immature connotation. You probably wouldn't want to stick someone with those names for life. Michael is more of a neutral canvas.

The same thing happens with Richard, who could end up nicknamed Rich, Richie, Ricky, Rick, Dickie, or Dick. If you love the name Richard but don't want your kid to be called Dick, it's prudent to tell people when he's born that the official nickname will be ___ and hope for the best. James can end up Jamie, Jimmie, or Jim. Elizabeth can end up Liz, Lizzy, Liza, Libby, Busy, Izzy, Betsy, Bess, Beth, Bethy, Betty, Birdie, Ellie, and probably several other nicknames. If you like some options more than others, it's smart to let people know that from the beginning.