When a host doesn't have an owner set (it happened to me, when I created fake host via console,
the failure to send notification prevented the host to be destroyed and no useful message was provided:
everything seemed fine, except the host was still there.

I believe the failures in notifications should not influence the functionality of the operation itself.

2017-03-17T17:41:04 e59c76c5  [app] [D] Setting current user thread-local variable to admin
2017-03-17T17:41:04 e59c76c5 [user:admin] [app] [D] Setting current organization thread-local variable to none
2017-03-17T17:41:04 e59c76c5 [user:admin] [app] [D] Setting current location thread-local variable to none
2017-03-17T17:41:04 e59c76c5 [user:admin] [notifications] [W] Invalid owner for aaron-brangers, unable to send notifications
2017-03-17T17:41:04 e59c76c5 [user:admin] [notifications] [D] Notification event: Hosts::MissingOwner - checking for notifications
2017-03-17T17:41:04 e59c76c5 [user:admin] [app] [I] Failed to save:
2017-03-17T17:41:04 e59c76c5 [user:admin] [app] [I] Redirected to http://localhost:3000/hosts