When you start to make a plan you can't focus on only one part of it. You have to consider everything that needs to be done so that you at least know what needs to be done. If you focus on only one thing even if it is the most important part you won't do everything it takes. And while you're planning be sure to plan on all the hard work as well as all of the steps to get there. Even if the one thing you focus on you did well it would be like building an engine to a car yet you have no wheels.