Why do I get 'couldn't create scheduler from policy' after applying a custom scheduler policy?

Issue

• Changes to schedulers.config.openshift.io are not processed and the kube-scheduler ClusterOperator is degraded.

• After applying the custom scheduler policy, kube-scheduler status message in the WebGUI or CLI shows an error:

  $ oc describe ClusterOperator kube-scheduler
  NodeInstallerDegraded: 1 nodes are failing on revision 42:
  NodeInstallerDegraded:
  StaticPodsDegraded: nodes/ip-ip-10-0-0-1.example.com pods/openshift-kube-scheduler-ip-10-0-0-1.example.com container="kube-scheduler" is not ready
  StaticPodsDegraded: nodes/ip-ip-10-0-0-1.example.com pods/openshift-kube-scheduler-ip-10-0-0-1.example.com container="kube-scheduler" is waiting: "CrashLoopBackOff" - "back-off 5m0s restarting failed container=kube-scheduler
  

• The affected pod of the kube-scheduler which is in the CrashLoopBackOff state is logging errors like:

  I0603 15:06:20.213665       1 factory.go:137] Creating scheduler from configuration: {{ } [{NoVolumeZoneConflict <nil>} {MatchNodeSelector <nil>} {MaxEBSVolumeCount <nil>} {MaxGCEPDVolumeCount <nil>} {MaxAzureDiskVolumeCount <nil>} {MatchInterPodAffinity <nil>} {NoDiskConflict <nil>} {GeneralPredicates <nil>} {PodToleratesNodeTaints <nil>} {CheckVolumeBinding <nil>} {Region 0xc0002f6d70}] [{SelectorSpreadPriority 12 <nil>} {InterPodAffinityPriority 12 <nil>} {MostRequestedPriority 3 <nil>} {BalancedResourceAllocation 12 <nil>} {NodePreferAvoidPodsPriority 120000 <nil>} {NodeAffinityPriority 12 <nil>} {TaintTolerationPriority 12 <nil>} {Zone 24 0xc000282180} {PriorityA 12 0xc0002821a0} {PriorityB 10 0xc000282200} {PriorityC 8 0xc000282a20} {PriorityD 6 0xc000282a60} {PriorityE 4 0xc000282aa0}] [] 0 false}
  couldn't create scheduler from policy: [LabelPreference  priority "PriorityB" has a different weight with "PriorityA", LabelPreference  priority "PriorityC" has a different weight with "PriorityA", LabelPreference  priority "PriorityD" has a different weight with "PriorityA", LabelPreference  priority "PriorityE" has a different weight with "PriorityA"]