Drill vs. Skill/Tactic success or failure

I came across a video from The Art of Coaching thanks to a student in one of my courses. At its core it has a similar message as the one from Karch in my What percentage of reps should be good? post. That has to do with having a success rate threshold that you don’t want to go above, generally. The idea there is that some amount of failure is required for learning and development.

Karch and Kerry from the video both recommend about a 30% failure rate. Or to put it another way, they want to cap success at about 70%. Putting players in that zone is about making them uncomfortable to facilitate growth.

Drill failure

Now, having said that, Kerry introduces – perhaps inadvertently – the question of the success of the drill itself vs. the succes of the actual thing the drill is working on. He did this by exploring a hitting drill that begins with a serve. In order to get to the attack, the players need to be successful at the serve, pass, set sequence leading up to it. Kerry was fine with the 30% failure rate here.

The video is a bit unclear as to whether Kerry targets a 30% failure rate, or whether he simply accepts one up to that level.

As I talk about in The Perfect Drill, a key objective of a training exercise is to give the players reps focused on something specific. To my mind, not being able to do that thing is a failure of the drill in that instance. Such failures are inevitable, of course. The question is the acceptable rate of those failures. Each one means missing out on a chance to perform the focus skill or tactic, after all.

Stacked execution failures

If Kerry actually targets a 30% failure rate for the serve-pass-set part of the hitting drill, to my mind he’s creating a stacked set of exercises, with potentially challenging consequences. We start with the players succeeding 70% of the time to generate the necessary set. Then the hitter(s) only succeed 70% of the time. That means overall the drill has a 49% success rate (0.7 x 0.7).

How do you think the players will react to only about a 50% overall success rate? How will you as a coach?

No doubt it depends on the group and the situation.