I have created a draft Cluster Configuration. When I select "Pre-Check Status", the pre-check fails on all hosts on the check "Checks if the host is ready to enter maintenance mode."

Following this article from Broadcom, I removed some Host-VM affinity rules. Yet the error still appears. I was able to put several hosts into maintenance mode through the vCenter interface. However, the cluster configuration pre-check still fails with the same error.
Is there anything else that could cause this check to fail?
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