The most important stories to do first are the ones that contain the highest business value. Beware of sequencing stories based on technical dependencies. Most of the time the dependencies are less important than the value.
One of the key parts of planning is deciding in what order you should do things. There is never any shortage of things to do. What should we do today?
Sometimes software is just too complicated, so instead let's consider something that is both more mundane and more essential. In cooking you answer this question by looking at the timing and sequencing in the recipe. Often there is quite a strong ordering involved: You have to fry the onions golden before you put in the chicken.
This notion of ordering ...