I disagree. In my own experience, working long hours is rarely a reliable way to produce excellent work or develop expertise. If anything, constraining hours is

I disagree. In my own experience, working long hours is rarely a reliable way to produce excellent work or develop expertise. If anything, constraining hours is a better approach. Yes, there are side-effects to any strategy, and often the side-effects from long hours (e.g., burnout, damaged relationships) are far more serious than the side effects of working too little. If there is a lack of progress due to not working enough, my first inclination is to think of ways to work smarter. When I worked long hours, and there was a lack of progress, my first inclination was try working even longer hours.