Frame your 'difficult experience' in a positive light, providing the situation involved, how you dealt with it, and what you learned. Detail what you would've done differently and how you avoided repeating it. Provide an example centered on the challenge, and how you overcame it, even if you didn't succeed to the degree you hoped. What is important are the gains that contributed to greater success moving forward.

"A while back, a supervisor told me I was the frontrunner for a promotion. This filled me with all sorts of heightened expectations. I told my spouse, and we celebrated. A few days later, they promoted someone from another department. The supervisor who told me this false information didn't really have a reliable source of information. It was just wishful thinking on their part. In the end, it was my fault for getting ahead of myself, and it isn't a mistake I'll lightly make again."