Catchable flies are worse than uncatchable flies. Though the uncatchables leave you longing to trap them or clap them in your hands, the catchable ones make you realize what happens when you fish your wish. All of a sudden, there's a fly in your fist and you're wondering why exactly you thought that was what you wanted. Killing it would involve dead-fly hands and releasing it would leave you longing to catch it again. Turns out flies are a lot like boys in some ways. Also, they both dislike being hit with fly-swatters.