Decisions decisions
When any messaging system sends messages, there will be errors. Even though the name servers do check the health of brokers beforehand, there is always delay. Plus, a network outage can happen during the transmission. But the handling of errors can be different.
The CAP Theorem is a fundamental theorem in distributed systems that states that any distributed system can have, at most, two of the following three properties: Consistency, Availability, and Partition tolerance. The following diagram shows the tradeoffs: