Well, a lot of pros started out using V-mount because something they own needed it. It was a reliable way of powering devices when there wasn't mains power available.Nowadays, V-mount is chosen by photographers and videographers as a way to power their cameras, monitors, and other devices. A single V-mount battery can power multiple devices, so it means that you don't need to worry about keeping an eye on multiple batteries, swapping them when they get low and keeping them all charged up. You just have a single battery to care for.