Yes this is a great idea then we just have to update out [FAQ][1] with this that  

>You can't upvote your own post even it is answer or question  

Or community can point out with a separate FAQ like 

>**Why I'm unable to see the Vote button on my own post while others posts I can?** 
  
 and the answer could be more powerful then mine 

>You can't vote to your own post so you are not able to see those buttons for your own posts.


  [1]: http://superuser.com/faq#reputation