I’ve seen so much stuff on what it means and how it affects people but I can’t find anything on the reason behind why anyone wants to shut down the government
I would note that the USA is about the only place this is actually possible.
In pretty much all other democracies, if the parliament fails to pass the budget bill, it triggers a dissolution of both houses and an election is held.
We need that in the USA too
as @Travalaaaaaaanche! mentioned, it’s just a form of brinksmanship – they don’t care “how it affects people” so long as they get their way
Mom gives you a weekly grocery list with $50 worth of products on it. You must buy everything on it every week.
Mom tells you to take $150 out of her wallet every month. You may not take any more.
You know you’ll be short. She knows you’ll be short. But you can get by for three weeks, so she’ll wait until then to address the issue.