We got a feedback from the support team that it is confusing to see switch in the Notifications column for the Alerting rule which have no alerts associated to it as user can not silence the Alerting rule. 

1. oc apply -f https://gist.githubusercontent.com/vikram-raj/727629797eb9d9bfcfa2721cae2ade86/raw/7c2305e14115a1a4f4f88ebb74cdad32cbec4132/Alerting%2520rule%2520without%2520alert 
2. navigate to the Developer perspective Observe -> Alerts
3. Try to silence the VersionAlert alerting rule, nothing will happen 

Silence the alerting rule using the switch will do nothing

No switch for silence the alerting rule should be visible if no alerts are associated to the alerting rule.