You'll have to know how to setup and maintain your own database infrastructure, though, right? I'm not an infrastructure engineer, but patching, security, OS updates, database software updates, being able to quickly redeploy in case of failure, redundancy, etc.

I've read horror stories about the poor engineers at AWS who are on call and have to detail with physical pagers paging them at various hours of the night. Systems fail, dependencies fail, shit happens... So now you will need to hire some small team to do these things for you.

I'm not saying you never need to be concerned with any of these things if you're on Azure or AWS.

I am saying that you need to factor in these components into your costs.

Infrastructure management might not be a core competency at my company. That's why I pay some premium but hand it off to the Azures and AWS's of the world.

Is hosting your own database cluster at some other company for a smaller monthly fee actually saving you money each month? What are the other costs to your business from making the move?

The answer could be yes, it's cheaper and makes 100% business sense. All I'm saying is these questions have to be asked, investigated and concluded. Arguing on one side or another without going through these steps is shortsighted.