What a container actually is
A packaged filesystem and process definition sharing the host kernel. It is not a virtual machine, which is why it starts in milliseconds and costs almost nothing to run.
Where the benefit shows up first
Identical environments across development, staging and production. The class of bug caused by a different PHP or library version simply disappears.
Where teams overreach
Adopting orchestration before they have more than a few services. Kubernetes solves problems of scale and failure that a two-server deployment does not have, and brings operational complexity that a small team will feel every week.
