To avoid interference between user application and theirs? Kinesis has pretty delicate throttle per shard and having user application that is out of their control working off the same shard will probably make the Firehose part much more fragile.<p>If you&#x27;re already doing all the Kinesis shard management&#x2F;KCL willy nilly why not just dump it to S3 yourself? Firehose seems to be targeting users who don&#x27;t want to deal with sharding.