Managed services cannot be beat for moving quickly on infra that is not a part of your core competency. Because winding down is as simple as shutting down the instances.

But the point about saving not even right. It costs a lot in staffing to set up some of this infra, and if you're a serious company (revenue and expectant customers), you're going to need redundancy on these things anyway, so its more than 1 person (they can be responsible for multiple things)