The female lays her eggs in flight, for example, like an insect bomber aircraft, while the males sometimes lay on an extraordinary show to attract a mate. The fly in pendulum-like movements over a particular spot, at the same time emitting a rather goaty smell. Females are duly attracted. In the mothy world as well as our own, it clearly takes all sorts.
Can you see the little face peeping over the back of the second Burnished Brass, above? That's a micro-moth snuggling up alongside. It's easier to see from the other side, here: