The reason is that a hawk always starts its flight with a small race on Earth. Without space to run, not even attempt to fly and will remain a prisoner for the rest of his life in this small jail homeless.
The bat, remarkably agile creature in the air, you can't leave a level place. If placed in a completely flat floor, all he can do is walk so confused, painful, looking for some slight elevation from which to launch.
A drone, if it falls in an open pot, stay there until you die or be removed. He doesn't see the output on high, therefore, persists in trying to get the sides near the bottom. Looks for a way out where there is no, until I die from all the shooting at the bottom of the glass.
There are people as the Hawk, the bat and the Bumblebee: they doggedly against obstacles, without realizing that the exit is just above, a look from a different point of view and only a prayer away.