When you apply an ActiveMQArtemis custom resource and you have defined some custom annotations (because you might need them for any purpose), those annotations are propagated to the StatefulSet, but they are not propagated to the PODs managed by the Statefulset.

apiVersion: broker.amq.io/v2alpha5
kind: ActiveMQArtemis
metadata: 
  annotations: 
    my.annotation/custom: myvalue
spec: 
  adminUser: adminuser
  deploymentPlan: 
    size: 2
:
:
: 

All annotations configured explicitly in the custom resource should be propagated to every running POD as well. In the example above, the pods should be annotated with my.annotation/custom: myvalue

For example, one common use case is to declare Prometheus annotations (if you're not declaring a Servicemonitor) to scrape your PODs, this way:

annotations: 
  prometheus.io/path: /metrics
  prometheus.io/port: 9404
  prometheus.io/scheme: http
  prometheus.io/scrape: "true"