When you've been to thousands of these things, you'd probably do the same thing.

For now, I'm going to keep it as headcanon that this right here is the only reason she wanted Discord reformed.

Considering we've yet to actually see a reason. (I thought it'd be to help make Twilight an Alicorn, but we all know how that turned out.) So this is it. She thought ahead and realized she couldn't rely on Twilight and her friends to destroy everything this year, so she decided to give Discord a second chance.