A strength, on the other hand, is an “activity that makes you feel strong.” This sort of activity possesses for you certain definable qualities. Before you do it, you find yourself actively looking forward to doing it. While you are doing it, time seems to speed up, one moment blurring into the next. And after you’ve done it, while you may be tired and not quite ready to suit up and tackle it again, you nonetheless feel filled up, proud. It is this combination of three distinct feelings—positive anticipation beforehand, flow during, and fulfillment afterward—that makes a certain activity a strength. And it is this combination of feelings that produces in you the yearning to do the activity again and again, to practice it over and over, to thrill to the chance to do it just one more time. A strength is far more appetite than ability, and indeed it is the appetite ingredient that feeds the desire to keep working on it and that, in the end, produces the skill improvement necessary for excellent performance.

Of course, if we were able to watch a great athlete training, or a great writer writing, or a great coder coding, we would see that honing a strength is hard work—it is by no means easy to find that incremental margin of performance when you are already operating at a high level—and that a strength is not where we are most “finished” but in fact where we are most productively challenged. Yet we are told to resist the temptation to “just” play to our strengths, and instead to work constantly on our weaknesses. In common parlance, we are told to avoid “running around our backhand.” This betrays, perhaps, a misunderstanding of what a strength actually is. It is not, for each of us, where performance is easiest—it is where performance is most impactful and increasing.

The 20 percent number was a threshold, which is to say that a little love goes an awfully long way: when you can deliberately weave your red threads throughout the fabric of your work you’ll feel stronger, perform better, and bounce back faster.

These red threads are your strengths. Typically we think of our strengths as what we’re good at and our weaknesses as what we’re bad at, and that our team leaders, or our colleagues, are therefore the best judges of both. But as we saw in chapter 4, this is not the best definition of either strengths or weaknesses. A strength is any activity that strengthens you (for Miles the anesthetist, keeping a patient hovering between life and death), and a weakness is any activity that weakens you, even if you’re good at it (for Miles, helping patients recover). “Performance” is what you have done well or poorly, and your team leader can be the judge of that. Team leaders and colleagues, however, can’t judge what strengthens or weakens you.

To say someone is doing something effortlessly is to betray ignorance of the effort they put into it.

I was unable or unwilling to give patience or understanding, so I expected her to give things. In an attempt to compensate for my deficiency, I borrowed strength from my position and

authority and forced her to do what I wanted her to do. But borrowing strength builds weakness. It builds weakness in the borrower because it reinforces dependence on external factors to get things done. It builds weakness in the person forced to acquiesce, stunting the development of independent reasoning, growth, and internal discipline. And finally, it builds weakness in the relationship. Fear replaces cooperation, and both people involved become more arbitrary and defensive.