I'm a very fast learner and generally learn things after one repetition. Unfortunately, I had to sit through three days of training this summer for a major upgrade to our database system. Just from messing around in the upgraded test environment before the trainer got there, I had pretty much figured out to configure everything and make it work the way I wanted it to. That three days felt like TORTURE and there were things I knew that our trainer did not. It was very hard to stay still and quiet so that the others in the room could learn.
Been there.
My boss wanted me to create a multimedia presentation to advertise our data services at the next tech convention, and she assigned me to take a 2-day, instructor-led HTML class the department offers regularly to assist. I figured I'd pick up a few tricks, since I'd done everything informally on my own before then, and this needed to look professional, so, sure.
Rather than having canned slides, the teacher would create code examples in a text editor on the fly, then open them in a browser to see the results. The results were rarely what he intended, and he could never find his syntax errors. Out of sheer frustration, I found myself having to direct him how to fix them. If I hadn't, nobody would have ever learned anything.