Better describe what type of changes are included in this list

Resolves #16

README.md

@@ -1,7 +1,9 @@
 # aws_breaking_changes
 [![feed](https://github.com/SummitRoute/aws_breaking_changes/raw/master/screenshots/feed_icon.png)Atom feed](https://github.com/SummitRoute/aws_breaking_changes/releases.atom)
 
-List of changes announced for AWS that may break existing code due to deprecations or otherwise. 
+My goal is to only document issues that would break people's existing applications. So if you have a running app on AWS that makes use of some AWS API calls, what are changes AWS is making that require you to change your code, reconfigure, rebuild, or redeploy your application? Can it live forever as long as your credit card works, or is AWS potentially breaking something?  
+
+Any change has the potential to break something somewhere, but these seem like the more impactful changes for those that use the impacted service.  These items will stay in this list until about a month after they have gone into effect, at which point they'll be removed.
 
 | Date taking effect | Date announced | Service | Change | How to check |
 | ---- | ---- |---- |---- |---- |