The first of Todd Henry’s everyday acts of bravery: Define your battles.

When we say choose your battles in the context of life or parenting, we mean we can’t win every time, and trying to is a sure way to accomplish nothing. So we choose which battles to spend our energy on, in the hopes that a few important wins will make up for the times we chose not to fight.

Defining our battles in creative terms is much the same. As artists and artisans, we define our work in terms of what we do–but trying to do everything leads to shoddy and unfinished work. If we wish to create art, or show ourselves experts in our fields, we must say no to more tasks than we say yes to. We must achieve mastery in a few areas rather than adequacy in all. I was happy to have a master surgeon operating on my colon last year, but I would not want him operating on my heart or spine, nor would he agree to do so.

In his brilliant book Outliers, Malcolm Gladwell asserts mastery of a field requires us to spend ten thousand hours working in that field. The examples he uses range from hockey players to computer giants to Manhattan lawyers to music stars. In all cases, they spent at least ten thousand hours–five to ten years–developing their craft before the opportunity that catapulted them to worldwide fame. Overnight success, it appears, requires five to ten years of preparation.

You can be sure anybody who spends ten thousand hours over ten years mastering one area is saying no to quite a few other options. They are choosing their battles, choosing to focus on one thing rather than a dozen others. Stephen King writes horror novels. Russell Crowe plays the soft-spoken action hero. Oprah gets people to share their inspiring stories. Each is a master of their chosen craft–and would be awful at the others.

And therein lies the risk of defining our battles. Every time we say no, every time we choose to focus on mastery, we accept the risk that our expertise may not be needed at the critical point. How many Stephen Kings have gone unknown because the gatekeepers wanted mystery instead of horror? Even more frightening, how many because Stephen King got his ten thousand hours first and the gatekeepers don’t need more horror?

It’s tempting, considering the risks, to stay a generalist, to say yes to as many opportunities as possible to avoid specializing in the wrong area. Adequacy in many areas seems safer than mastery in one or two–and when the call comes in one area, we tell ourselves, we can specialize then.

But the days are gone when people, and especially companies, were willing to sponsor adequacy. The market demands mastery now. Courage lies in defining our battles today, so that when the market needs a master in our field, we will be ready.