It seems a lot of people have forgotten how BigCorp IT used to work.

- request some HW to run $service

- the "IT dept" (really, self-interested gatekeeper) might give you something now, or in two weeks, or god help you if they need to order new hardware then its in two months, best case

- there will be various weird rules on how the on-prem HW is run, who has access etc, hindering developer productivity even further

- the hardware might get insanely oversubscribed so your service gets half a cpu core with 1GB RAM, because perverse incentives mean the "IT dept" gets rewarded for minimizing cost, while the price is paid by someone else

- and so on...

The cloud is a way around this political minefield.