First, think back to a decision you’ve made that you either now see as a bad decision or that you’re still not fully sure you thought through critically. It doesn’t have to be a super-personal decision (why did I date that guy for so long in high school?), and it can even be a decision that’s had a good outcome (why did I choose Winthrop?), as long as you can express how you didn’t really think critically about it at the time.