Regrettably, you're going to die. As far as that goes, you don't have much choice. But your death may involve a lot of other decisions, and perhaps you'd like to be the one to make them.
Would you prefer to die at home, for example, instead of in the hospital? If you fell into a coma with no expectation of recovery, would you want to be kept alive regardless? When you become unable to make those choices, who should make them for you?