Fix explanation: the Effect action creates a new ref on each call

src/Effect/Ref.purs

@@ -21,8 +21,9 @@
 -- | In the above code, `first` would be the same as `second` if it upheld
 -- | referential transparency. However, `first` holds the same reference twice
 -- | whereas `second` holds two different references. Thus, it invalidates
--- | referential transparency. By making `Ref.new` return an `Effect`, a
--- | new separate reference is created each time.
+-- | referential transparency. By making `Ref.new` return an `Effect`, we
+-- | return an _action_. Each time this action is called, it will create a new
+-- | separate reference that is initialized to the given value.
 -- |
 -- | In regards to the second, consider the below example:
 -- | ```