IMO that's not why they _really_ do it. They have limits on everything because even at their scale they can't instantly accommodate your needs to suddenly scale or they need to prevent "noisy neighbor" situations where your sudden excessive usage impacts others' workloads. They still have to do relatively short term capacity planning to accommodate you. Like, I work for only a medium-large sized company and AWS has quoted us lead times of _weeks_ to make the instances we need for a workload available. We only needed 200-300 EC2 instances and they weren't even super unusual types. I think their infinite scaling on a dime claims are pure marketing jibber jabber.