The summary.
THE SPECTRUM
Software: you use an application. Platform: you deploy code. Infrastructure: you run machines.
Control and responsibility rise together as you move down.
THE RULE FOR CHOOSING
Take the most managed option that does what you need.
Every layer you manage is a layer you must maintain and secure.
WHAT MOST SMALL BUSINESSES ACTUALLY NEED
Software services, and ordinary hosting for their website.
Raw infrastructure looks cheaper per unit until you count the administration time.
THE WARNING ON VIRTUAL SERVERS
An unmaintained virtual server is worse than shared hosting. Establish who maintains it before choosing it.
ON SERVERLESS AND CONTAINERS
Genuine capabilities that most small businesses do not need.
For simple automation, a scheduled task on existing hosting is usually sufficient.
THE MISCONFIGURATION THAT MATTERS MOST
A database reachable from the internet. Check what is actually exposed after creating anything.
BEFORE ADOPTING ANY MANAGED SERVICE
Establish how you would export your data and leave. Provider-specific services are the hardest dependencies to unwind.