add back why section to readme

README.md

@@ -21,6 +21,9 @@ invariant(falsyValue, 'This will throw!');
 // Error('Invariant violation: This will throw!');
 ```
 
+## Why `tiny-invariant`?
+`tiny-invariant` is a *tiny*, widely-supported, zero-dependency alternative to [`invariant`](https://www.npmjs.com/package/invariant). See [below](#Dropping your message for kb savings!) for details on just how compact it can get.
+
 ## Error Messages
 
 `tiny-invariant` allows you to pass a single string message. With [template literals](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Template_literals) there is really no need for a custom message formatter to be built into the library. If you need a multi part message you can just do this: