Want to work better? Work less, say researchers at the OECD, who have discovered an interesting correlation between how much you work and how productive you are: working longer hours results in a reduction of labour output.
It runs contrary to American work ethic. Work harder and you will succeed. The truth may be somewhat different. We tend to burn out at some point. Little is accomplished and little is learned. Ask any college student. There is a point at which more studying becomes fruitless.