Terraform drift detection is often misunderstood as automatic repair logic.
The real mechanism starts earlier.
Terraform first reads remote infrastructure reality through the provider. That refreshed data is then compared against stored state and desired configuration. Drift becomes visible only after Terraform reconciles those relationships.
This lesson breaks apart:
- remote reality
- Terraform state
- desired configuration
- refresh-only behavior
- correction planning
The lesson also explains why Terraform cannot detect every infrastructure change and why unmanaged resources remain outside drift visibility scope.