Lights don’t occur at ground level at night in nature. The closest thing is the moon. Night flying insects use the moon to orient themselves and navigate, never thinking they will actually get there. If a moth were to fly, attempting to keep a light bulb “moon” over its left shoulder, for instance, it would fly in circles around the bulb. The slightest change in angle would send it spiraling away or toward the light bulb until: CRASH! The moth slams into its moon! Of course, insects are not adapted to land on their moon and without a mechanism to deal with the situation. They are over stimulated, sitting with their wings vibrating. Come morning, they are exhausted, fall to the floor and look for the nearest hiding place, under your door. In the morning, you open the door and they are in!