I had a student who was ready for a bit more of a challenge, so I put her on a nice, but could-be-cranky pony. This pony usually needed a bit of encouragement to go, so students needed to carry a crop when riding her, but she would buck if they used it. I told the student this. So what does she do? Smacks the pony when it won't trot and promptly gets bucked over the arena fence. It was her first fall, too. lol She was fine, just surprised. I said 'maybe next time you'll listen to me when I tell you not to use the stick'. Lesson learned.