Automatic Drupal Security Updates

For a long time, the community has tried to somehow implement automatic Drupal security updates.
There exist a few scripts to automate Drupal updates and some Drupal hosting providers even offer them. But which way would be the "right" way of doing it? Is there an universal solution for this or does it require projects to have a certain setup?

In this session, I will present a possible solution for automatic security updates which is git friendly and based on Composer.
Wouldn't it be nice to simply receive a text or email with the content "All your Drupal security updates have been processed."?