It can be hard to find interesting books on strategy. Most of the ones I read were pretty boring. However, On Grand Strategy, offered some insight into the way people think and what made some leaders successful and other fail. Much of it had to do with their ability to be a fox and a hedgehog.
The fox is a person who changes with the times and uses cues from his environment to make decisions. They are able to see the world as it emerges and make fast paced decisions. They are not always right but they do adjust to the environment.
The hedgehog makes very slow decisions and often gets stuck in a particular way of thinking. They have a hard time adjusting to changes but do have a long-term strategy.
To be the most successful it is necessary for people to have a long-term strategy like the hedgehog but to be able to adjust while keeping those goals in mind like the fox. You don't want to adjust every day and you don't want to never be adjusting.
In today's work environment it is important to ensure that you are able to work to your environment but still stay focused on your goals. Think of a company that must think 10 years down the road but still must deal with day to day changes in their environment. A successful strategy will have a little of both.