Explain why not to prefix methods with underscores

Author: ttmarek

react/README.md

@@ -450,6 +450,7 @@
     ```
 
   - Do not use underscore prefix for internal methods of a React component.
+  > Why? As Doug Crockford writes: "Do not use _ *underbar* as the first or last character of a name. It is sometimes intended to indicate privacy, but it does not actually provide privacy. If privacy is important, use closure. Avoid conventions that demonstrate a lack of competence." Source - http://javascript.crockford.com/code.html.
 
     ```jsx
     // bad