I haven't seen this listed explicitly (though Doc Brown's answer touched on it, regarding version numbers), but IMHO the single most important part to get right in a release process is the Configuration Management. You should to be able to identify exactly what artifacts were deployed, and be able to reproduce those artifacts on demand from source.

If a customer comes to you with a bug, you'll really want to know precisely the source under which the bug was created.

I haven't seen this listed explicitly (though Doc Brown's answer touched on it, regarding version numbers), but IMHO the single most important part to get right in a release process is the Configuration Management. You should to be able to identify exactly what artifacts were deployed, and be able to reproduce those artifacts on demand from source.

If a customer comes to you with a bug, you'll really want to know precisely the source under which the bug was created.