When the Web TimeSheet application was initially implemented, certain e-mail notifications were disabled in the system, by the Web TimeSheet administrator for specific business requirements however later, the administrator decides to enable them since it is a necessity now. The administrator goes ahead and enables the e-mail notifications from the global settings under Administration > left panel > Communications > E-mail Notifications but is not sure if the global settings would suffice or would it also require to enable them under the individual user profiles too.
The moment a new user is added to Web TimeSheet, all the e-mail notifications are enabled in the user's profile, by default and hence when a disabled e-mail notification is enabled from the global setting, it is automatically available for the newly added user or existing users to use it. Let's assume that you have already gone under a user's profile and have manually unchecked all e-mail notifications and then have enabled a disabled e-mail notification from the global settings under Administration > left panel > Communications > E-mail Notifications, this time the enabled e-mail notification isn't automatically available for the user since e-mail notifications have been already forcefully disabled from the user profile. In such scenarios the e-mail notifications have to be manually enabled under the individual user profiles.