Tbh like 99% of web apps aren’t critical - most of them are for buying something or providing infrastructure to make it easier to buy something anyway. It’s fine if your online shop is down for a few minutes (of course the business won’t see it like that but it’s true)

A sales site being down might lose you a sale. But the simplicity might save you so muh more than that loses you. And often the complexion of high availability infrastructure results in more downtime than it prevents.

For stuff like HN, I like the peek behind the scenes it provides. It's all just software written by some humans and way too often people take themselves and their shitty software way too serious.