Why does CaliberRM fail to send out an email notification when a new requirement is created?
Follow the instructions in the this article Setting up CaliberRM email notifications to ensure that email notifications are configured correctly.
There is also often confusion as to when an email will be sent once a new requirement is created. When a user creates a new requirement, they must first select a user within the "Responsibilities" tab before saving. This "Responsible" user will then receive an email to notify them that a new requirement has been created. If a user is not set as responsible before saving, then no notification will be set.