Use Delete When
You truly want the resource gone and do not want the controller definition to remain.
You are cleaning up temporary or obsolete workloads.
Compare
kubectl delete vs scale to zero
How to choose between removing a workload entirely and temporarily stopping it.
Deleting a workload removes the object itself. Scaling to zero keeps the object definition but stops its running replicas. Those are very different operational choices.
Use Scale to Zero When
You want to pause a workload without deleting its definition.
You expect to bring the service back by scaling it up later.
Rule of Thumb
Delete removes. Scale to zero pauses.
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