Building a business on blank cheques and accidental spends is shady. It's also a large barrier to adoption. The more times devs see reports like, "I tried [random 20-minute tutorial] and woke up to a bill for my life's savings and luckily support waived the fee this one time but next time they're coming for my house", the less they'll want to explore your offerings.
You have reached your Configured Maximum Monthly Spend Limit.
As per your settings we have removed all objects from S3, All RDS Databases, All Route53 Domains, all ESB volumes, all elastic IPs, All EC2 instances and all Snapshots.
Please update your spend limit before you recreate the above.
Yours, AWS
It wouldn’t solve the problem for usage-based billing, but it would have solved the problem here.
There's always a dunning period and multiple alerts
Also you have variable costs (like s3 traffic) that could put you over your limit half way through the month. Then how does AWS stop you breaching your limit?
On a more practical level I don't think AWS keeps tracks of bills on a minute-by-minute basis.
Sort of related, another wishlist feature I have is a way to start an EC2 instance with a deadline up front, and have the machine automatically suspended or terminated if it exceeds the deadline. I have some programs that start an EC2 instance, do some work, and shut it down (e.g. AMI building), and I would sleep a tiny bit better at night if AWS could deadline the instance as a backstop in case my script unexpectedly died before it could.
> Also you have variable costs (like s3 traffic)
Yeah, that's what I mean by it wouldn't solve the problem of usage-based billing. There they could just cut you off, and I think that's the bargain that people who want hard caps are asking for (there is always a spend cap at which I'd assume something had gone horribly wrong and would rather not keep spending), but I agree that the lack of real-time billing data is probably what stops them there.
Having one AWS account where you actually run stuff, and one that follows the rule of "if it can't be paved and recreated from github, don't put it there" is exactly how a lot of people do it anyway.