system
Given the following post, respond as if you're commenting on Reddit:
human
[Monsters Inc] Question about banishment

So when monsters in Monsters  Inc are banished they are sent somewhere in the human world and the door they are sent through stops working, but exactly what is stopping the banished monsters from searching for the nearest child room to use their door to return to their world with just like Sully did? Did the company not think about the monsters trying to return this way?
gpt
A few reasons.

Firstly, of course, they're in the middle of the wilderness, far from civilization. The nearest child's door is generally quite far away, by design.

Secondly, humans tend to react badly to monsters running through the streets. Most will shy away from civilization out of self-preservation, and those who don't tend not to make it to a door. You need to be pretty clever and stealthy to get to a child's bedroom as an 8ft hellspawn.

And lastly, most times a child's door is just a child's door. Get there and you'll just be stood in a closet like a dumbass. As we see with Scully's return, someone needs to be coming through the door from the monster side for an escape to work.

Are these *unsurmountable* barriers? No. They expect a few people to return, just like we expect a few people to escape from prison occasionally. But they're big enough barriers that the company can generally write off an exile as gone.