Let's use your driving example (because car examples are always great!)...
>You want to waste money? Hire a car, with a driver, when you need it.
>Want to save money. Learn to drive.
This is true. You can save more money if you need to drive often if you own a car. But there are two scenarios that it still makes sense to rent.
1) What if you need a car in a different city? You just flew from JFK to SFO. You already have a car in NYC, but need one in SF. You're not going to buy a car in SF that you'll need to sell in a week. Sure, if you're going to be there longer, you might consider it, but then you're still carrying the costs of two cars.
2) Sometimes you need a truck. Maybe you have an IKEA run to make to get a bunch of desks, or stop at the hardware store for a few dozen bags of mulch, or ... But sometimes you just need a truck to get the job done. You could just buy a truck and be done with it. But trucks can be more expensive than a compact car, and they definitely have higher fuel costs. In this case, you'd probably be better off with a fuel efficient (or electric) compact car and rent a truck only when you need it.
This is how you save money with the cloud. But you definitely don't save money when you effectively rent a truck to drive to work everyday (even if you are in construction). There is a cost to renting -- it is more expensive on a per-use basis than it is if you buy. Cloud servers are more expensive than bare metal -- if you're constantly using them. It is only cheaper when you stop paying for the parts you don't need. And that also takes expertise.
Once, at a new job, I inherited a cloud server. It was costing us a ton of money per month and running 24/7 because the person who set it up never turned it off. After 3 months of those costs, they could have bought a new server with no other renting. They paid for a cloud server for three reasons: 1) they had no experience with hardware, 2) it was a pain to setup local hosting, and 3) it was faster to get running without waiting for a vendor to build a server, deliver it to the datacenter, etc... These were real impediments to the first person and the cloud server helped to get them moving. They just didn't have the longer term view of what their decision was going to cost in the long term.
The first thing I did was order a new server and make friends with our datacenter ops people. And now the only thing we really use the cloud for is archival (write-once, read-never) storage. If we ever really need these data, it will be super expensive. But, if that ends up happening, we'd be happy to pay the cloud tax.
