I had a friend who knew how to hold chopsticks but could never eat with them. They had never figured out that the bottom chopstick is never moved. Confused when I mentioned this, they had trouble trying to hold one chopstick still while moving the top one. Finally, I said something that turned the whole situation into a much more enlightening moment:

The thumb is the fulcrum.

Within moments, they could use the chopsticks.

I'm a bit embarrassed that I may have been using them incorrectly at the time. Eating at a Chinese restaurant not too long ago, I bothered to read the wrapper that my chopsticks came in. I had most of the steps correctly, but as the label points out, now you can pick up anything. So I tried to pick up the table. It didn't work. I'm not sure where I went wrong with the chopsticks, but someday I'll get it.