One great example. We were paying $45k/yr for a hosted MS Dynamics GP solution. For $26k we brought it in house with only a $4k/yr maintenance fee. We bought a rackmount Dell, put on VMWare, have an app VM and a DB VM. My team can handle basic maintenance. In the past 11 months we haven't had to touch that server once. We have an automated backup, pulls VMs out daily and sends them off to Backblaze. Even if we need to call our GP partner for some specialized problem, it's not $45k/yr in consulting costs.
We had a bunch of Azure servers for Active Directory and a few other things. When I came in 2 years ago I set up new on-prem DC VMs, and killed out absurd Azure monthly bill, we were saving money by month three. A meteor could take out Atlanta and the DCs are our satellite offices would handle the load just fine until we restored from backups and we'd STILL save money. We've had MORE uptime and reliability since then too.
If I have a server go down, we have staff to get on it immediately, no toll free number to dial, no web chat to a level 1 person in India, etc.
Our EMR is hosted, because that's big enough that I want to pay someone to be in control over it, and someone to blame. However, there have been many times where I'm frustrated with how they handle problems, and jumping from one EMR to another is not easy. And in the end they're all bad anyway. Sometimes I DO wish we were self hosted.
The Cloud is just someone else's computer. If they're running those machines more cheaply than you are, they're cutting out some cost. The question is, do you need what they're cutting?