We don't have to bother ourselves with managing SANs, managing bare metal, managing hardware component failures and FRUs, managing PDUs, managing DHCP and PXE boot, managing load balancers, managing networks and VLANs, and managing hypervisors and VMs. We don't have to set up NFS or object stores.

Being on a mature managed service platform like AWS means that if we want 10 or 100 VMs, I can ask for them and get them in minutes. If I want to switch to beefier hardware, I can do so in minutes. If I want a new subnet in a different region, I can have one in minutes. There's simply no way I can have that kind of agility running my own datacenters.

Nobody disputes that AWS is expensive. But we're not paying for hardware or bandwidth qua hardware or bandwidth - we're paying for value added.