I keep telling customers: "The cloud will scale to the size of your wallet."

They don't understand what I mean by that. That's okay, they'll learn!

Anyway, this kind of thing comes up regularly on Hacker News, so let's just short-circuit some of the conversations:

"You can set a budget!" -- that's just a warning.

"You should watch the billing data more closely!" -- it is delayed up to 48 hours or even longer on most cloud services. It is especially slow on the ones that tend to be hit the hardest during a DDoS, like CDN services.

"You can set up a lambda/function/trigger to stop your services" -- sure, for each individual service, separately, because the "stop" APIs are different, if they exist at all. Did I mention the 48 hour delay?

"You can get a refund!" -- sometimes, with no hard and fast rules about when this applies except for out of the goodness of some anonymous support person's heart.

"Lots of business services can have unlimited bills" -- not like this where buying what you thought was "an icecream cone" can turn into a firehouse of gelato costing $1,000 per minute because your kid cried and said he wanted more.

"It would be impossible for <cloud company> to put guardrails like that on their services!" -- they do exactly that, but only when it's their money at risk. When they could have unlimited expenses with no upside, then suddenly, magically, they find a way. E.g.: See the Azure Visual Studio Subscriber accounts, which have actual hard limits.

"Why would you want your cloud provider to stop your business? What if you suddenly go viral! That's the last thing you'd want!" -- who said anything about a business? What if it's just training? What if your website is just marketing with a no "profit per view" in any direct sense?