Lets suppose you are launching a new line of business. It's a bit of a punt. You hope it will be wildly successful but equally it might not.

Do you invest in new hardware, licencing, resilience and failover capability for everything needed to operate this new line of business?

Perhaps you should spin it up in the cloud, determine what the demand is. Run it long enough so that the natural ebbs and flows of business are determined and you have genuine sizing and capacity metrics then bring it back in house.