[londons_explore]

I understand that designing a real-time billing system is near impossible.

But couldn't Google/Amazon simply pretend they have real-time bill capping, and then simply swallow the costs incurred by any delays?

Doesn't seem like rocket science, probably won't cost much, and might bring in new kinds of business (a lot of businesses won't allow most employees to sign an effectively blank check)

[sigotirandolas]

To avoid penalizing customers who don't use it, they could make you incur an instant overcharge fee when you go over your limit, say 5% of your limit, which would be pooled to compensate for any extra cost Amazon could need to incur to salvage customer data. Like an insurance, fundamentally.

Now that I think about it, a third party could do this as well... except that if it were built in to AWS there would be much less friction.