Error creating a topic with 10k partitions but not altering existing topic to 10k partitions? Why

Hi – just curious if anyone can suggest why the following occurs:

1 – try to create a topic with 10,000 partitions with Kafka CLI (kafka-topics.sh)
Fails with ERROR org.apache.kafka.common.errors.PolicyViolationException: Unable to perform excessively large batch operation.

2- create a topic with 1 partition with Kafka CLI, and alter to 10k partitions - works fine

Paul