The life plan is intended to transform your life into what you value the most through who you are, what you do, and what you have.
Often our desires contain mutually exclusive things, but almost no one realizes when the many things they desire compete with one another. Making your priorities explicit helps you see when the pursuit of one thing you want detracts from the pursuit of another, because as you spend the extra time and thought elucidating how to obtain what you want the most, you will also see previously hidden conflicts in what it will take to get what you want almost as much.
A great deal of resources are wasted on low value pursuits because people make the mistake of comparing the value of what they choose to doing nothing. The reality is that the cost of every moment is the highest value action that could occupy it. Most choices fail to measure up when compared against the potential action of greatest worth. Every decision in life is a tradeoff, and far more often than you realize, there tends to be something within the set of possible choices of much greater worth than any other option.
The best way to improve your choices is to spend more time thinking about them before you make them, ideally when you are far away from the situation in which you’ll need to make them. The more time you put into making and rehearsing detailed prioritizations of what you value, the more likely you will be to follow those prioritizations in the moment of choice.