In the United States, thousands of people die each year while on the transplant waiting list. Even those that do have agonizingly long waits for their new organ(s), often while on life support. During this time, the patient's health deteriorates (sometimes resulting in their priority status being lowered), which results in a protracted recovery or often death, and expensive life support is required, often costing tens of thousands of dollars per day.
The current system, which faces us with an organ shortage, is "opt-in," so donors must consent. Some nations have an "opt-out" system, so that by default, healthy adult candidates are automatically registered as organ donor candidates. This presents a much greater pool of candidates, as evidenced by Austria's rate of almost 100%.