It's almost impossible to talk meaningfully about someone's performance as a whole ("Nicola, I thought you did great last year"). So instead most performance conversations are broken down into chunks & at CSB we call these chunks factors. For example a factor might be a hard performance metric, like sales, or a softer behavior, like teamwork. People typically get a rating on each factor, and there are a million different types of rating scales, which many smart people have put lots of effort into designing. But for the purposes of this coaching idea the actual rating scale is, er... kind of irrelevant.
And this is why...
Imagine you have a rating scale from 1 to 10 (like I said it really doesn't matter), you're dealing with a factor of teamwork, and your employee Nicola has rated herself a 5.
The best way to get to the absolute core of understanding how Nicola views her contribution to teamwork is not to ask her to explain why she is a 5. It's to ask her why she isn't a 4.
Why? Because that forces her to think about the incremental stuff she did: the things that made a difference. Which is a lot more specific, and a lot more useful. It also tells you the things that Nicola thinks are important for this factor.
The best part is that this then sets you up for the obvious follow up question: Why weren't you a 6?
Why is this a cool question? Because it allows you to start the development discussion. What are the tangible things that she could have done better? Can we work together to do those things from now on?
You don't need to use this approach for every factor, but its particularly useful if you and your employee have a difference of opinion. If that ever happens!