The two factor authentication process that Apple initiated a few years ago has become commonplace by now, but you might choose to reduce this complexity and turn off two factor authentication from your account for a variety of reasons too.
For many of us, email is a necessary email. Email makes our student and professional lives significantly easier, as a way of sending and sharing information. Not everything can be sent in a text, Facebook or WhatsApp message, or using Snapchat or Slack.