The Infernal Revenue Service Wants You To Make Mistakes On Your Return.

http://www.nytimes.com/2010/01/24/business/24digi.html
Why Can’t the I.R.S. Help Fill in the Blanks?

Consider, your w-2s, 1099s, ... are all filed with the Infernal Revenue Service. Any forms that are submitted manually, are digitized. Many forms are already submitted electronically.

So why doesn't the Infernal Revenue Service send out preprinted forms with the submitted information already filled out? I can think of one reason off the top of my head. The Infernal Revenue Service wants you to make mistakes on your return. If you make mistakes on your return, the Infernal Revenue Service is never going to figure that out in a reasonable period of time. Which means that you not only get a penalty for not being able to figure out how to prepare your return correctly, they can also add interest to the amount of underpayment from the day the return was filed!

Seems like a good scam to me.