I hope to address how having an addendum to your application whether it is to highlight an academic hiccup or academic strength or nuance is important to share!
This question is truly significant for many applicants. This is where YOU as the applicant can address any red flags, “pink elephants in the room” or just emphasize a particular passion or talent you may have. An example of a red flag would be a downward grade trend or one bad grade in a core class. “Pink elephants in the Room” are usually a little more nuanced-- it could be an academic sanction you’ve been dealt or a civil liberty arrest that you underwent (protesting and getting arrested for it).
Whatever it might be, use this question to frame your response to focus on the positives and strengths and away from the weaknesses or negative nuances of your application.
If your background warrants an explanation this is the time to state it but frame it in a way that will not harm your chances of gaining admission. Such as: “I am a true lover of learning and exploring the world around me and I am excited about the [mention something specific and relatable to the university]. In the past I have had a momentary lapse of good judgement but I have been completely humbled and have used this momentary lapse as a way to mentor other students who may be in the same situation."
Perhaps you would like to highlight a major achievement that is important to you. Do it without restating the obvious points. Use this space to talk about your passion from a new dimension. For example, “Although I briefly mentioned it on my application, my opportunity to do XYZ was important to me because ...... My ability to do XYZ made me ....... and this is something I will bring to campus at your school.”
It is ok to share a positive here- as long as it is done tastefully and without an arrogant tone. Every student should take advantage of this optional addendum.