Why should Kafka consumers be idempotent?

Question

Why should Kafka consumers be idempotent?

Option A — Correct answer

Because at-least-once delivery can produce duplicate processing

Option B

Because Kafka never stores offsets

Option C

Because partitions cannot be ordered

Option D

Because consumers cannot retry

Explanation

Duplicates are normal in many failure/retry scenarios.

Quiz: Kafka Consumer Design and Reliability