We overvalue what is easily observed. When assessing someone’s performance, either during a review or when considering promotion, we will bias toward information that is simple and obvious. In my experience, that means overvaluing accomplishments that are greater in number or more diverse in nature. What we then undervalue is the quality of the accomplishment. For example, we will see more value in a manager who runs a large team adequately compared to one who runs a small team well. We’re more impressed by someone who does three different things than we are by the person who does one thing three different times.

This can combine negatively with the desire for novelty. The unpleasant fact is that mastery of any complex skill is not just difficult, it’s boring. It doesn’t matter whether it’s verifying accessibility compliance, managing to a budget, or writing a code generator. For many people, a new skill is interesting at the start, but it starts getting boring once they’re decently good at it. Being really, really, really good at something means pushing far beyond the point of boredom, either via necessity, obsession, or discipline.

Having someone who is world class in an important skill can be incredibly valuable. Getting them can be hard, because sometimes the major payoff doesn’t come when they’re merely good. If you also reward dilettantism, then you’ll create a disincentive to develop that expertise. Find a way to observe and make evident when someone is amazing at something.