One of the most important parts of being an effective leader is choosing what to spend your time on. Just as important is choosing how much time to spend on it. The difference between the most effective leaders and everyone else isn’t that they’re smarter or harder-working. The difference is that they squeeze much more out of every hour they spend by focusing their energies where they can get the most impact for the effort.

The simplest way to understand this leverage is to look at every important project under way and assess what its current odds of success are. With rare exceptions, you ignore anything that’s likely to succeed. Those don’t need your time.

Instead, what needs your time are the projects that are probably going to fail. From those projects, choose the ones where you can improve their chances. The ones where you can’t, well, cancel those. With the ones that can be saved, you have a simple goal: take them from “probably going to fail” to “probably going to succeed.” Once you do that, you exit stage left and don’t come back.

This simplification is, like most simplifications, wrong. But it’s not that wrong. Any time you are considering putting your scarce time into something, ask yourself two questions. The first is whether the project is already likely to succeed. The second is, if it’s not, whether you can realistically hope to make it a probable success.

You can invest in probable successes and in likely failures and improve the odds. That may be worth it. But you need to think about what is losing your energy and attention for you to do that. There’s a nearly infinite number of things you can do, but everything you choose to do comes at the cost of what you don’t have time to do. If you invest your time into projects where you have low leverage, then you’re probably ignoring projects that would really benefit from your attention, whose paths can be changed.