Unlike email, alerts will reach you wherever you are. If you are online when an important event occurs, you will be notified instantly with a pop-up message on your screen. If you are not online, the alert will be sent to your mobile phone. If you have not setup a mobile phone then alerts will be delivered to your email box so you never miss an important event.
Alerts signal that an important message has been sent. It's not the kind of routine communication someone might receive as email. Alerts cut through the clutter.