How to properly set up and track email traffic in Google Analytics?

Question

Email Marketing

In Google Analytics, one of the most important reports is the Traffic Channels report. The most basic traffic channels are as follows:

• organic search
  
• direct
  
• Referral
  
• Social
  
• Email
  

As far as I understand, GA sorts all visits through these channels automatically, if we do not interfere with our personal UTM tags. But as far as I understand, the email channel is not automatically created. No traffic is visible here by default, or even the channel itself is not visible. Traffic starts to be written to this channel only if we put a UTM tag in the emails utm_medium=email.
Can you tell me why GA doesn't automatically generate an email channel while it does other channels? Or what needs to be done, where to set what settings for this to start happening?

Answer 1

Mark up all your links. Always. Necessarily.
Use shortened links where long links look bad.
This will save you from "lost" visits and misunderstandings with traffic channels.
If the traffic is more than 20 people per day, markup is a must.
This is my opinion and it is backed up by experience.
It is much more pleasant to spend a couple of hours once to learn how to semi-automatically tag all links than to spend days and weeks analyzing sessions automatically distributed by analytics systems that come from nowhere.
The versatility of your own markup will allow you to build summary reports across different channels with similar attributes, for example, to analyze the effectiveness of one or another call to action in advertising, etc.
Mark up all your links. Always. Necessarily.
And be happy.

Answer 2

Create a default channel group at the profile level, to which add all referrals that contain the word mail.