This clip from The Boxtrolls both discusses and shows us how animation works. In it, the Boxtrolls begin to wonder about the nature of their existence just as the animator who is controlling them comes into view, revealing the grueling process at work.
In this clip, the Boxtrolls begin to wonder about free will.
"What if our world is a tiny speck? And there are giants looking down on us?" they ponder. Just then, the animator is revealed to be manipulating their every movement.
What if "every time we move, it's actually them moving us?" they ask, as we pan out to see the larger set.
"Seems a bit tedious. Like that, there. Me blinking. That would've taken them a day," they continue. Indeed!
The Boxtrolls are right, animation is definitely a lot of effort. This small clip seemed to take days, judging by the animator's changing outfits. In the end, though, it sure is worth it.