When asked, most people will admit that they are afraid of death. Some are more concerned with physical or mental deterioration that goes with the process, others are afraid that it will be painful. Many however are more afraid of dying before they accomplish what they intend to do during their life. They are afraid of the time running out. Hence, so many people are maintained on life support machines at the end of their life process despite the fact that the recovery is unlikely or that suffering is getting worse and worse.
Life or Death by Dr. Sergey Sorin
Why do so many people and their family members cling to staying alive at any cost?
A part of the answer lies in cultural upbringing and individual belief systems; the other, more basic component has to do with how one lives their life. If a person has followed their calling and is satisfied with what they accomplished and more importantly, performed the service to others, which they feel they should, the dying process itself becomes simply a transition.
In different cultures and belief systems there are different paths that the souls journey will take place and even if one chooses not to believe that there is anything after death, still there is a satisfaction with having lived a fulfilling life, no matter how long or short, and death is just another stage or a transition point.