Dragonflies spend most of their lives in the larva stage (up to three years, depending on the species). The adult, winged stage only lasts a few weeks. Mating is the primary reason for their winged stage. So when you see a winged dragonfly, you know it's toward the end of its lifespan. Sad but true.
Though you can't see them all with the naked eye, the compound eyes of the dragonfly can contain thousands of tiny lenses. Because of their large, multifaceted eyes, the adult dragonfly can see nearly 360 degrees around it at all times.