Fridge / Wool

• A major aspect that ends up being used as Foreshadowing: the silo, in spite of being a futuristic setting for speculative fiction, is massively and peculiarly inefficient. Travel and even communication both depend on the extremely low-tech stairwell, which takes days to go down, even though the silo is supplied by massive machines and a silo-wide digital network. And the cleaning suits always break down at the exact same place, even though they’ve been developed for years. Why? It’s all built-in-obsolescence; IT’s goal isn’t advancement or efficiency, it’s stagnation and preservation.
  • The TV adaptation confirms that the Pact specifically prohibits mechanization of transit within the Silo. No lifts, no pulleys, just human legs. Everyone (or nearly everyone) has accepted that the Founders must have made that rule for a good reason and they should not question it. And it worked. When rebellions do break out, usually in the lower levels, IT has plenty of time to hunker down and mount a defense because it's going to take the rebels days to actually get to them.
• IT’s stubborn insistence on still having their energy not cut when an energy holiday is declared to fix the generator. Why? Not because they need it; because they want to hide the fact that they have a separate energy source in case of rebellion.
• Another potential Foreshadowing moment from information added in the show: the Pact prohibits magnification beyond a certain power. This would make it impossible for residents to build any kind of handheld computer or camera, because the necessary wiring is way too small to be done without pretty extreme magnification. But it would also prevent silo residents from accidentally stumbling upon the bio-weapon nanobots that triggered the fake apocalypse in the first place and are heavily implied to still be circulating in all of the silos.
• The only cameras in the Silo are the one used to take ID photos and the one used to keep an eye on the outside world. The idea of a photograph, and certainly the idea of a computerized image, is completely foreign to Silo residents. So it would never even occur to anyone that the projection of the outside world could be faked, or even that such a thing would be possible. Unless you happen to stumble upon the code IT has been using to do it.
• In a very twisted way, the sabotaged cleanings are set up perfectly. IT can't actually let anyone survive their cleaning—if they do, that proves that the Silo has access to the resources needed for some degree of survival in the outside world, and suddenly there will be lots of questions asked about why we aren't out there if we can get outside safely. So the cleaner has to die. But they also don't want to look too incompetent, and they have to give the impression that they gave the cleaner their best shot at surviving. (And how else can they justify requisitioning all of the very best materials in the Silo, if not by the pretense that they're being used for the suits?) The suits are set up to allow the cleaner to live for just a few minutes—just long enough to let them get the cleaning done, show the fancy technology to the residents and make it look like the Silo did try to help them survive outside, but then oh no, it's still so dangerous out there that even all of our very best efforts were ultimately in vain.