How would this actually work? Actually think a bit about how hard it would be to add a global, synchronised and immediate view of an accounts cost and check it on every single API call.

Take S3 for example: you set a 1$ limit then concurrently upload 10 1$ per month files. What happens? Should 9 of those uploads fail? How would you ever synchronise that? Or perhaps they complete, but should the bucket delete the contents after the ”storage cost per hour” limit is reached?

Perhaps you could reconcile the account cost usage every hour, and when reached the account should be locked somehow and no new writes or reads can be done on anything. Which is basically breaking the account and everything that runs on it. Most people don’t want that.

How would it even work with bandwidth? You’re serving a file from S3 or EC2 with your 10$ account limit. What happens after you use 10$ bandwidth? Should your accounts external internet connection be cut off? How would you even calculate that cost in real time at scale.

Use your brain. AWS are not stupid. It’s a minefield of complexity that would be super expensive to implement and that benefits nobody. The “if you mess up we will refund you up to 2 times” policy works absolutely fine.