Although I knew they existed, I used to think that kids who got kicked out (or whose acceptance was rescinded) were something like mythical creatures because it took so much effort to mess up that badly. I doubted anyone could ever fall to that level. Over the course of the past few years, however, I did witness a handful of suspensions/expulsions and rescindings from various institutions and summer programs. Their stories are listed here.
In my sophomore year of college, a friend and I became sort-of-friends with a guy who worked at our favorite boba tea shop. He worked there every day, and told us he took classes at Foothill Community College. I went back to college after Christmas break ended, but the boba tea guy kept texting both me and my friend from afar, and we finally found out his secret. He'd been an extremely talented art student who was accepted into RISD (Rhode Island School of Design), one of the top art colleges in the nation. However, he stopped showing up to high school classes after being accepted, failed several subjects, and had his acceptance instantly rescinded by his dream school.
When I was in high school, one of my classmates was suspended from school for doodling on a scantron for a California State Standardized Test, taking a photo of it, and posting it on Facebook. It wasn't the greatest decision, but his fate is a good example of what happens when you're not careful with social media. Our whole American Studies class was on a spring break trip in the southern states (visiting famous sites from the Civil Rights Movement) when he found out, and the first half of the trip was an awkward combination of our teachers giving this student angered/disappointed looks and other students not knowing what to say to him. He was almost sent home from the trip, but eventually was allowed to accompany us until the end with limited privileges and close monitoring.
Getting kicked out or having your acceptance rescinded can happen as a result of many other factors: plagiarism, cyber-bullying, serious rule violations (or even minor rule violations, depending on how strict the program is), and surfacing of past secrets (especially scandalous or criminal-related secrets). While this may never happen to you, it's good to remember to keep a clean record, because you never know what will come back to haunt you in the future.