Corrected entry: When Wall-E sees the one red light, he chases it as it seems to have a mind of its own. Later we find out that this red light belonged to a group of red lights from a space ship, so how did this red light escape on its own?
bobthedancingdonut
26th Nov 2015
Correction: The red light (along with the others) is a tracking device meant to guide the ship to the landing point. All of the lights likely start out as seemingly random, then gradually track to the correct location, getting less random as they go.