From the new LEGO mag (no, I don't have it; I got this from a scan and transcript):
Q: Do you have a favorite Character?
A: My favorite character is Click. In the original script the unnamed scarabax beetle was supposed to change into a shield and stay that way for the whole film. I thought it would be fun to give the beetle the ability to change back and forth and also give him a name. That way, Mata Nui would have a little companion to take along his journey.