diff --git a/salt/states/pip_state.py b/salt/states/pip_state.py
index 24262831ea..e8cb7906d4 100644
--- a/salt/states/pip_state.py
+++ b/salt/states/pip_state.py
@@ -136,6 +136,12 @@ def installed(name,
         This usually means having the system's pip package installed or running
         Salt from an active `virtualenv`_.
 
+        The reason for this requirement is because ``pip`` already does a
+        pretty good job parsing it's own requirements. It makes no sense for
+        Salt to do ``pip`` requirements parsing and validation before passing
+        them to the ``pip`` library. It's functionality duplication and it's
+        more error prone.
+
     .. _`virtualenv`: http://www.virtualenv.org
     '''
     if pip_bin and not bin_env: