Nature's Idiot -- The Dodo Bug

This little guy is the stupidest thing I have ever seen. I honestly don't know how they ever evolved into anything. I've seen them when they're out in the open; they hover like hummingbirds and they hum like them too. I can hear them at night, pelting my door. Mini and incessant battering rams with the clatter of fire crackers. It's a marvel, the strategy they employ to infiltrate my room. They zoom, full speed, into the door; fall down; and then crawl around until they've walked through the gap at the bottom of my door. They're fast when they're flying but it doesn't seem like they stay in the air for that long. If they are airborne for more than 30 seconds they run into the wall, or a table, a chair, and then drop to the ground. They're their own pest control. I'll wake up in the morning and they've bashed their own brains out and then all I have to do is sweep them out the door.
            I'm also completely unaware of their purpose. They don't have a stinger, they don't swarm around in hives, or hover over flowers. What do they contribute? I suppose they little birdies need something to eat.