• what-is-linux-stable.md gives an overview of what linux-stable is and how it came about.
• why-is-linux-stable-important.md gives some reasons why this is important and addresses some of the excuses that people give for not caring about it (when they definitely should).

I also recommend reading all of this info from Greg Kroah-Hartman himself, at the following links:

• https://lkml.org/lkml/2018/3/22/560
• https://lkml.org/lkml/2018/3/22/647
• http://kroah.com/log/blog/2018/02/05/linux-kernel-release-model/