These alerts fire without a namespace label:
* KubeStateMetricsListErrors
* KubeStateMetricsWatchErrors
* KubeletPlegDurationHigh
* KubeletTooManyPods
* KubeNodeReadinessFlapping
* KubeletPodStartUpLatencyHigh

Alerting rules without a namespace label make it harder for cluster admins to route the alerts.

4.13

Always

1. Check the definitions of the said alerting rules.

The PromQL expressions aggregate away the namespace label and there's no static namespace label either.

Static namespace label in the rule definition.

https://github.com/openshift/enhancements/blob/master/enhancements/monitoring/alerting-consistency.md#style-guide

Alerts SHOULD include a namespace label indicating the source of the alert. Many alerts will include this by virtue of the fact that their PromQL expressions result in a namespace label. Others may require a static namespace label