We almost always are.*
One measure of a person’s capacity to make a deep contribution to your team is their ability to go into a situation for which they are inadequately prepared and still do good work. They show up, they listen and observe, they make connections and create possibilities, they apply your shared values in context, and most of all they serve.
Everyone makes mistakes, but a teammate who consistently causes damage unless they’ve been exhaustively prepared – and sometimes even when they have been – is a teammate who shouldn’t be representing you.
*Sometimes we’re not even sure what we’re inadequately prepared for.