Unhealthy warning message : Readiness probe failed

Hi all,
Have one unhealthy warning message happened when deleting one istio-ingressgateway pod and toggles between ready and readiness states that message is shown “Readiness probe failed: Get http://{istio-ingressgateway-pod-IP}:15021/healthz/ready"dial tcp {istio-ingressgateway-pod-IP}:15021: connect: connection refused”.

Although a warning message occurred, it’s no longer appears after the pod is become to ready.
Does the warning message mean abnormal or normal?
Does anyone have the same problem ?