Cleaning Up.

At the end of each semester and the end of each year it's a good time to clean things out. Purge the negativity in your life. Get rid of things that don't bring you joy. Purge the negative emotions. 

And if you're Batman, purge the city of criminals. 

It's that last reason that always kept Batman from applying for grad school. Fighting crime doesn't leave a lot of time for homework or group projects.