> if I run my "build" processes (npm, composer, etc) on the server at deploy time
It's perfectly fine, as long as you accept the risks and downsides. Your IP can get ratelimited for Docker Hub. The build process can exhaust resources on the host. Your server probably needs access to internal dev dependencies repository, thus, needs credentials it would not need otherwise. Many small things like that. The advantage is simplicity, and it's often worth the risk.
> IP ratelimited for Docker Hub
How? What I'm describing is using Docker less.
> The build process can exhaust resources on the host
Maybe, but I've yet to have a host where that's the case for usual CRUD fare.
> The advantage is simplicity, and it's often worth the risk.
That's basically what I'm evaluating for here.
For bog standard LAMP or similar stack applications, I've not understood the advantage of going through the build-image-then-pull-on-host rigmarole. There's more layers involved there than something like provisioning with Ansible and just having a deploy script to run the usual suspects.
But I have seen that done fairly often, hence was wondering what the point was.