The Terraform Knows What It Should Provision At All Times.
the terraform knows what it should provision at all times. it knows this because it knows what it hasn’t provisioned.
by subtracting what is from what ought to be (or what ought to be from what is, depending on provider drift), it obtains a plan, or diff.
the planning subsystem uses diffs to generate imperative operations to drive the infrastructure from a state that is, to a state that isn’t, and in arriving at a state that wasn’t, it now is.
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