Repeat practicing can be helpful in solidifying a shaky spot, with two caveats: First, it’s easy to play a lot of mistakes if your only goal is a lot or repetitions. Second, playing over-and-over without good focus (I call it robot practicing) can lead you to a lot of wasted time.

To prevent this, we will set a goal of only five repetitions, but they must be excellent. We will also severely punish mistakes by resetting to zero. The combination of a low number of repetitions and serve punishment leads to more focused repetitions and fewer mistakes.