I don't understand why the IRS requires us to send in a W-2 with our returns when filing on paper, but have no need for the W-2 if you file electronically.
For example, when my youngest daughter was in college, she worked numerous part time jobs. When it came time to file, I would do her taxes for her, trying to keep everything in order and providing the correct W-2(s) for the correct forms (Fed, State, School in Ohio). However, I would depend on my wife to mail them in for us as she goes into the office every day while I work from home.
Well, a couple of times, she mixed up the W-2s (even though I have everything paperclipped together). A couple of months later, we got a letter from the IRS stating that my taxes were in error because the W-2(s) provided didn't account for the total taxes due for the year. So I would get all of the copies out and go through and discovered that they must not have received the correct W-2. I would then have to fill out the correct forms, send the W-2 in and HOPE that they applied it correctly.
But had my daughter filed electronically, none of this would have mattered. Frustrating.
NOTE: It was not worth the cost to file electronically as her return was less than the amount of the cost.