Book by Gary Keller published in 2013
This is a great book on a subject I've thought a lot about in the past. It introduced some new mental model that are useful. It got me to think about a lot of interesting things. My reason for not giving this book the fifth star is that it's not completely grounded in reality always. It advocates for always focusing on one thing in work, and embracing the chaos that results in—but lacks examples of what that looks like and how to deal with the problems of saying nos. Is it really true you should never stray from your one thing? Can't that occasionally lead to something great? If everyone is focusing on their one thing, and no-one is helping each other, is that really scalable and sustainable? These questions I would've liked to see processed in the book. That said, the usage of the Pareto principle, the mental model of nested goals, why having big goals are important, that saying yes is saying implicitly no, etc., are all explored in great depth.